FlexShares Trust
FlexShares® Trust Prospectus
Fund Ticker Stock Exchange
FlexShares® US Quality Low Volatility Index Fund QLV NYSE Arca, Inc.
FlexShares® Developed Markets ex-US Quality Low Volatility Index Fund QLVD NYSE Arca, Inc.
FlexShares® Emerging Markets Quality Low Volatility Index Fund QLVE NYSE Arca, Inc.
FlexShares® Morningstar US Market Factor Tilt Index Fund TILT Cboe BZX Exchange, Inc.
FlexShares® Morningstar Developed Markets ex-US Factor Tilt Index Fund TLTD NYSE Arca, Inc.
FlexShares® Morningstar Emerging Markets Factor Tilt Index Fund TLTE NYSE Arca, Inc.
FlexShares® US Quality Large Cap Index Fund QLC Cboe BZX Exchange, Inc.
FlexShares® STOXX® US ESG Select Index Fund (formerly, FlexShares® STOXX® US ESG Impact Index Fund) ESG Cboe BZX Exchange, Inc.
FlexShares® STOXX® Global ESG Select Index Fund (formerly, FlexShares® STOXX® Global ESG Impact Index Fund) ESGG Cboe BZX Exchange, Inc.
FlexShares® ESG & Climate US Large Cap Core Index Fund FEUS NYSE Arca, Inc.
FlexShares® ESG & Climate Developed Markets ex-US Core Index Fund FEDM NYSE Arca, Inc.
FlexShares® ESG & Climate Emerging Markets Core Index Fund FEEM NYSE Arca, Inc.
FlexShares® Morningstar Global Upstream Natural Resources Index Fund GUNR NYSE Arca, Inc.
FlexShares® STOXX® Global Broad Infrastructure Index Fund NFRA NYSE Arca, Inc.
FlexShares® Global Quality Real Estate Index Fund GQRE NYSE Arca, Inc.
FlexShares® Real Assets Allocation Index Fund ASET The Nasdaq Stock Market LLC
FlexShares® Quality Dividend Index Fund QDF NYSE Arca, Inc.
FlexShares® Quality Dividend Defensive Index Fund QDEF NYSE Arca, Inc.
FlexShares® Quality Dividend Dynamic Index Fund QDYN NYSE Arca, Inc.
FlexShares® International Quality Dividend Index Fund IQDF NYSE Arca, Inc.
FlexShares® International Quality Dividend Defensive Index Fund IQDE NYSE Arca, Inc.
FlexShares® International Quality Dividend Dynamic Index Fund IQDY NYSE Arca, Inc.
FlexShares® iBoxx 3-Year Target Duration TIPS Index Fund TDTT NYSE Arca, Inc.
FlexShares® iBoxx 5-Year Target Duration TIPS Index Fund TDTF NYSE Arca, Inc.
FlexShares® Disciplined Duration MBS Index Fund MBSD NYSE Arca, Inc.
FlexShares® Credit-Scored US Corporate Bond Index Fund SKOR The Nasdaq Stock Market LLC
FlexShares® Credit-Scored US Long Corporate Bond Index Fund LKOR Cboe BZX Exchange, Inc.
FlexShares® High Yield Value-Scored Bond Index Fund HYGV NYSE Arca, Inc.
FlexShares® ESG & Climate High Yield Corporate Core Index Fund FEHY NYSE Arca, Inc.
FlexShares® ESG & Climate Investment Grade Corporate Core Index Fund FEIG NYSE Arca, Inc.
Prospectus dated March 1, 2022.
An investment in a Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (“FDIC”), any other government agency, or The Northern Trust Company, or its affiliates, subsidiaries or any other bank. An investment in a Fund involves investment risks, including possible loss of principal.
The Securities and Exchange Commission (“SEC”) has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

 


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Back Cover

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Fund Summaries
FlexShares® US Quality Low Volatility Index Fund

Investment Objective
The Fund seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the Northern Trust Quality Low Volatility IndexSM (the “Underlying Index”).
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Under the Fund’s Investment Advisory Agreement, the Fund is responsible for the following expenses: interest expenses, brokerage commissions and other trading expenses, fees and expenses of the independent trustees and their independent legal counsel, taxes and other extraordinary costs such as litigation and other expenses not incurred in the ordinary course of business. You will also incur usual and customary brokerage commissions and fees to financial intermediaries when buying or selling shares of the Fund in the secondary market, which are not reflected in the example that follows:
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fees 0.22%
Distribution (12b-1) Fees 0.00%
Other Expenses 0.01%
Total Annual Fund Operating Expenses 0.23%
Expense Reimbursement(1) -0.01%
Total Annual Fund Operating Expenses After Expense Reimbursement 0.22%
(1) Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than Acquired Fund Fees and Expenses) to the extent the “Total Annual Fund Operating Expenses” exceed 0.22%. This contractual limitation may not be terminated before March 1, 2023 without the approval of the Fund’s Board of Trustees. The Fund’s Board of Trustees may terminate the contractual agreement at any time if it determines that it is in the best interest of the Fund and its shareholders.
Example
The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5%
return each year and that the Fund’s operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year $23
3 Years $73
5 Years $129
10 Years $292
Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. Portfolio turnover may vary from year to year, as well as within a year. During the most recent fiscal year, the Fund’s portfolio turnover rate was 43% of the average value of its portfolio.
Principal Investment Strategies
The Underlying Index is designed to reflect the performance of a selection of companies that, in aggregate, possess lower overall absolute volatility characteristics relative to the Northern Trust 1250 Index (the “Parent Index”), a float-adjusted market capitalization weighted index of U.S. domiciled large- and mid-capitalization companies. In addition, the Underlying Index is designed to select companies from the Parent Index that exhibit financial strength, stability and enhanced risk-return characteristics, which Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) believes can provide equity-market participation while seeking to protect against downside risks during certain market environments.
To derive the Underlying Index, NTI, acting in its capacity as the index provider (the “Index Provider”) ranks all constituents of the Parent Index using a Northern Trust proprietary quality factor. This factor is a quantitative ranking based on: (a) management expertise (e.g. corporate finance activities); (b) profitability (e.g. reliability and sustainability of financial performance); and (c) cash flow (e.g., cash flow generation). The Index Provider then excludes the lowest quintile of constituents ranked accord- 
 

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FlexShares® US Quality Low Volatility Index Fund (cont.)

ing to the quality factor and uses an optimization process to select and weight eligible securities in order to (a) seek to reduce overall portfolio volatility and (b) maximize the overall quality factor relative to the Parent Index. The optimization also includes sector, industry group, single-security weight, historical beta (i.e. market sensitivity, relative to the Parent Index) and turnover constraints so that these characteristics of the Underlying Index vary within acceptable bands relative to the Parent Index. 
As of December 31, 2021, the Underlying Index was comprised of 110 constituent securities with market capitalizations ranging from $3.9 billion to $2.9 trillion. The Underlying Index is governed by published, objective rules for security selection, exclusion, weighting, rebalancing and adjustments for corporate actions. It is reconstituted quarterly. The Fund generally reconstitutes its portfolio in accordance with the Underlying Index. 
 NTI uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. 
NTI uses a representative sampling strategy to manage the Fund. “Representative sampling” is investing in a representative sample of securities that collectively has an investment profile similar to the Underlying Index. The Fund may or may not hold all of the securities that are included in the Underlying Index. The Fund reserves the right to invest in substantially all of the securities in its Underlying Index in approximately the same proportions (i.e., replication) if NTI determines that it is in the best interest of the Fund. 
Under normal circumstances, the Fund will invest at least 80% of its total assets (exclusive of collateral held from securities lending) in the securities of the Underlying Index. The Fund may also invest up to 20% of its assets in cash and cash equivalents, including shares of money market funds advised by NTI or its affiliates, futures contracts and options on futures contracts, as well as securities not included in the Underlying Index, but which NTI believes will help the Fund track its Underlying Index. 
The Underlying Index is created and sponsored by NTI, as the Index Provider. NTI also serves as the investment adviser to the Fund. The Index Provider determines the 
composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. 
The Fund may lend securities representing up to one-third of the value of the Fund’s total assets (including the value of the collateral received). 
The Fund is “non-diversified” under the Investment Company Act of 1940 (“1940 Act”), as amended, and may invest more of its assets in fewer issuers than “diversified” funds. 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. 
Principal Risks
As with any investment, you could lose all or part of your investment in the Fund, and the Fund’s performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.
Equity Securities Risk is the risk that the values of the equity securities owned by the Fund may be more volatile and underperform other asset classes and the general securities markets.
Low Volatility Risk is the risk that although the Underlying Index is designed to have overall volatility that is lower than that of the Parent Index, there is no guarantee it will be successful. Securities or other assets in the Fund’s portfolio may be subject to price volatility and the prices may not be any less volatile than the market as a whole and could be more volatile. The market prices of the securities or other assets in the Fund’s portfolio may fluctuate, sometimes rapidly and unpredictably. The Fund will continue to seek to track the Underlying Index even if the Underlying Index does not have lower overall volatility than the Parent Index. There is also the risk that the Fund may experience volatility greater than that of the Parent Index as a result of 
 

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FlexShares® US Quality Low Volatility Index Fund (cont.)

tracking error. A portfolio of securities with greater volatility is generally considered to have a higher risk profile than a portfolio with lower volatility. 
Quality Factor Risk is the risk that the past performance of companies that have exhibited quality characteristics does not continue or the returns on securities issued by such companies may be less than returns from other styles of investing or the overall stock market. There may be periods when quality investing is out of favor and during which time the Fund's performance may suffer. 
Concentration Risk is the risk that, if the Fund is concentrated in a particular industry or group of industries, the Fund is likely to present more risks than a fund that is broadly diversified over several industries or groups of industries. Compared to the broad market, an individual industry may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock or regulatory changes. 
Market Risk is the risk that the value of the Fund’s investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude of such changes in value cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, changes in interest rates, lack of liquidity in the bond or equity markets, or volatility in the equity markets. Market disruptions caused by local or regional events such as war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor sentiment could have a significant impact on the Fund and its investments and could result in the Fund’s shares trading at increased premiums or discounts to the Fund’s NAV. An outbreak of COVID-19, a respiratory disease caused by a novel coronavirus, has negatively affected the worldwide economy, the financial health of individual companies and the market in significant and unforeseen ways. The future impact of COVID-19 is currently unknown. The effects to public health, business and market conditions resulting from the COVID-19 pandemic may have a significant negative impact on the performance of the Fund’s investments. During periods of market disruption or other 
abnormal market conditions, the Fund’s exposure to the risks described elsewhere in this summary will likely increase. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track its Underlying Index or cause delays in the Underlying Index’s rebalancing or reconstitution schedule. During any such delay, it is possible that the Underlying Index and, in turn, the Fund will deviate from the Underlying Index’s stated methodology and therefore experience returns different than those that would have been achieved under a normal rebalancing or reconstitution schedule. Because the Fund is designed to maintain a high level of exposure to its Underlying Index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns. 
Market risk includes the risk that a particular style of investing, such as growth or value, may underperform the market generally. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global economies and financial markets. As a result, whether or not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected. Securities markets may experience great short-term volatility and may fall sharply at times. Different markets may behave differently from each other and a foreign market may move in the opposite direction from the U.S. market. 
Price changes may be temporary or last for extended periods. You could lose money over short periods due to fluctuation in the market prices of the Fund’s shares in response to market movements, and over longer periods during market downturns. 
Index Risk is the risk that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Underlying Index, even if that security generally is underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of an index. Additionally, the Fund rebalances and/or reconstitutes its 
 

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FlexShares® US Quality Low Volatility Index Fund (cont.)

portfolio in accordance with the Underlying Index, and, therefore, any changes to the Underlying Index’s rebalance and/or reconstitution schedule will result in corresponding changes to the Fund’s rebalance and/or reconstitution schedule. 
Tracking Error Risk is the risk that the Fund’s performance may vary substantially from the performance of the Underlying Index. The Fund’s performance may vary from the performance of the Underlying Index for a number of reasons including that the Fund incurs operating expenses that the Underlying Index does not and that the Fund accepts custom baskets. 
Sampling Risk is the risk that the Fund’s use of a representative sampling approach may result in increased tracking error because the securities selected for the Fund in the aggregate may vary from the investment profile of the Underlying Index. Additionally, the use of a representative sampling approach may result in the Fund holding a smaller number of securities than the Underlying Index, and, as a result, an adverse development to an issuer of securities that the Fund holds could result in a greater decline in NAV than would be the case if the Fund held all of the securities in the Underlying Index. 
Authorized Participant Concentration Risk is the risk that the Fund may be adversely affected because it has a limited number of institutions that act as authorized participants (“Authorized Participants”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. 
Calculation Methodology Risk is the risk that the Underlying Index’s calculation methodology or sources of information may not provide an accurate assessment of included issuers or correct valuation of securities, nor is the availability or timeliness of the production of the Index guaranteed. A security included in an Underlying Index may not exhibit the characteristic or provide the specific 
exposure for which it was selected and consequently a Fund’s holdings may not exhibit returns consistent with that characteristic or exposure. Unusual market conditions may cause the provider of the Underlying Index to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Market Trading Risk is the risk that the Fund faces because its shares are listed on a securities exchange, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS MAY LEAD TO THE FUND’S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of its listing exchange, make trading in the shares inadvisable. The market prices of Fund shares will generally fluctuate in accordance with changes in its NAV, changes in the relative supply of, and demand for, Fund shares, and changes in the liquidity, or the perceived liquidity, of the Fund’s holdings. 
Derivatives Risk is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instruments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments. 
Futures Contracts Risk is the risk that there will be imperfect correlation between the change in market value of the Fund’s securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of NTI to correctly predict the direction of securities’ prices, interest rates, currency exchange rates and other 
 

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FlexShares® US Quality Low Volatility Index Fund (cont.)

  economic factors, which may make the Fund’s returns more volatile or increase the risk of loss.
Options Contracts Risk Options contracts give the holder of the option the right to buy (or to sell) a position in a security or in a contract to the writer of the option, at a certain price. They are subject to correlation risk because there may be an imperfect correlation between the options and the securities markets that cause a given transaction to fail to achieve its objectives. The successful use of options depends on the investment adviser’s ability to predict correctly future price fluctuations and the degree of correlation between the options and securities markets. Exchanges can limit the number of positions that can be held or controlled by the Fund or the investment adviser, thus limiting the ability to implement the Fund’s strategies. 
Mid Cap Stock Risk is the risk that stocks of mid-sized companies may be subject to more abrupt or erratic market movements than stocks of larger, more established companies, and may lack sufficient market liquidity. Mid-sized companies may have limited product lines or financial resources, and may be dependent upon a particular niche of the market, or may be dependent upon a small or inexperienced management group. Securities of smaller companies may trade less frequently and in lower volume than the securities of larger companies, which could lead to higher transaction costs. Generally the smaller the company size, the greater the risk. 
Non-Diversification Risk is the risk that because the Fund is non-diversified and may invest a larger percentage of its assets in the securities of fewer issuers than a diversified fund, the Fund’s performance will be more vulnerable to changes in the market value of a single issuer or group of issuers, and more susceptible to risks associated with a single economic, political or regulatory occurrence. 
Securities Lending Risk is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. 
It is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit 
Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank.
Fund Performance
The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated information on the Fund’s performance results can be obtained by visiting flexshares.com.
Calendar Year Total Returns
For the period shown in the bar chart above:
Best Quarter (6/30/2020): 15.80%
Worst Quarter (3/31/2020): -18.55%
Average Annual Total Returns
(for the periods ended December 31, 2021)
  One
Year
Since
Inception
of Fund
Inception
Date
of Fund
Before Taxes 26.07% 16.74% 7/15/2019
After Taxes on Distributions 25.75%
16.38%
After Taxes on Distributions and Sale of Shares 15.62% 13.00%
Russell 1000® Index* 26.46% 22.52%
Northern Trust Quality Low Volatility IndexSM* 26.38% 17.05%
* Reflects no deduction for fees, expenses or taxes.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may dif-
 

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FlexShares® US Quality Low Volatility Index Fund (cont.)

fer from those shown. After-tax returns shown are not relevant to investors who hold shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement plans. After-tax returns may exceed the return before taxes due to an assumed tax benefit from realizing a capital loss on a sale of Fund shares.
Management
Investment Adviser and Portfolio Managers. NTI, a subsidiary of Northern Trust Corporation, serves as the Investment Adviser of the Fund. Robert Anstine and Brendan Sullivan, each a Vice President of NTI, have served as Portfolio Managers of the Fund since its inception in July 2019. Volter Bagriy, a Vice President of NTI, has served as a Portfolio Manager of the Fund since March 2021.
Purchase and Sale of Fund Shares
The Fund is an exchange-traded fund (commonly referred to as an “ETF”). The Fund’s shares may be issued and redeemed only by certain large institutions, referred to as “Authorized Participants,” that enter into agreements with the Fund’s principal underwriter. Retail investors may acquire and sell Fund shares in the secondary market through a broker-dealer. The price of Fund shares is based on market price, and because ETF shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the Fund (bid) and the lowest price a seller is willing to accept for shares of the Fund (ask) when buying or selling shares in the secondary market (“the bid-ask spread”). Recent information, including information about the Fund’s NAV, market price, premiums and discounts, and bid-ask spreads, is included on the Fund’s website at flexshares.com.
Tax Information
The Fund’s distributions are generally taxable to you as ordinary income, qualified dividends, capital gains, or a combination of the three, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account. Distributions may be taxable upon withdrawal from tax-advantaged accounts.
Payments to Brokers-Dealers and Other Financial Intermediaries
If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), NTI and its related
companies may pay the intermediary for activities related to the marketing and promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.
 

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FlexShares® Developed Markets ex-US Quality Low Volatility Index Fund

Investment Objective
The Fund seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the Northern Trust Developed Markets ex-US Quality Low Volatility IndexSM (the “Underlying Index”).
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Under the Fund’s Investment Advisory Agreement, the Fund is responsible for the following expenses: interest expenses, brokerage commissions and other trading expenses, fees and expenses of the independent trustees and their independent legal counsel, taxes and other extraordinary costs such as litigation and other expenses not incurred in the ordinary course of business. You will also incur usual and customary brokerage commissions and fees to financial intermediaries when buying or selling shares of the Fund in the secondary market, which are not reflected in the example that follows:
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fees 0.32%
Distribution (12b-1) Fees 0.00%
Other Expenses 0.01%
Total Annual Fund Operating Expenses 0.33%
Expense Reimbursement(1) -0.01%
Total Annual Fund Operating Expenses After Expense Reimbursement 0.32%
(1) Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than Acquired Fund Fees and Expenses) to the extent the “Total Annual Fund Operating Expenses” exceed 0.32%. This contractual limitation may not be terminated before March 1, 2023 without the approval of the Fund’s Board of Trustees. The Fund’s Board of Trustees may terminate the contractual agreement at any time if it determines that it is in the best interest of the Fund and its shareholders.
Example
The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5%
return each year and that the Fund’s operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year $33
3 Years $105
5 Years $184
10 Years $417
Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. Portfolio turnover may vary from year to year, as well as within a year. During the most recent fiscal year, the Fund’s portfolio turnover rate was 56% of the average value of its portfolio.
Principal Investment Strategies
The Underlying Index is designed to reflect the performance of a selection of companies that, in aggregate, possess lower overall absolute volatility characteristics relative to a broad universe of securities domiciled in developed market countries, excluding the U.S. (the “Parent Index”). The Parent Index is a subset of the Northern Trust Global Index, where eligible securities are limited to those domiciled in non-U.S. developed market countries and designated as large- and mid-capitalization companies by Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”), acting in its capacity as the index provider (the “Index Provider”). In addition, the Underlying Index is designed to select companies from the Parent Index that exhibit financial strength, stability and enhanced risk-return characteristics, which NTI believes can provide equity-market participation while seeking to protect against downside risks during certain market environments.
To derive the Underlying Index, the Index Provider ranks all constituents of the Parent Index using a Northern Trust proprietary quality factor. This factor is a quantitative ranking based on: (a) management expertise (e.g. corporate finance activities); (b) profitability (e.g. reliability and sustainability of financial performance); and (c) cash flow 
 

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FlexShares® Developed Markets ex-US Quality Low Volatility Index Fund (cont.)

(e.g., cash flow generation). The Index Provider then excludes the lowest quintile of constituents ranked according to the quality factor and uses an optimization process to select and weight eligible securities in order to (a) seek to reduce overall portfolio volatility and (b) maximize the overall quality factor relative to the Parent Index. The optimization also includes sector, industry group, country, region, single-security weight, historical beta (i.e. market sensitivity, relative to the Parent Index) and turnover constraints so that these characteristics of the Underlying Index vary within acceptable bands relative to the Parent Index. 
As of December 31, 2021, the Underlying Index was comprised of 185 constituent securities with market capitalizations ranging from $2.7 billion to $417.8 billion. The Underlying Index is governed by published, objective rules for security selection, exclusion, weighting, rebalancing and adjustments for corporate actions and is reconstituted quarterly. The Fund generally reconstitutes its portfolio in accordance with the Underlying Index. 
NTI uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. 
NTI uses a representative sampling strategy to manage the Fund. “Representative sampling” is investing in a representative sample of securities that collectively has an investment profile similar to the Underlying Index. The Fund may or may not hold all of the securities that are included in the Underlying Index. The Fund reserves the right to invest in substantially all of the securities in its Underlying Index in approximately the same proportions (i.e., replication) if NTI determines that it is in the best interest of the Fund. 
Under normal circumstances, the Fund will invest at least 80% of its total assets (exclusive of collateral held from securities lending) in the securities of the Underlying Index and in American Depositary Receipts (“ADRs”) and Global Depositary Receipts (“GDRs”) (collectively “Depositary Receipts”) based on the securities in the Underlying Index. The Fund may also invest up to 20% of its assets in cash and cash equivalents, including shares of money market funds advised by NTI or its affiliates, futures contracts, options on futures contracts and forward currency con- 
tracts, as well as securities not included in the Underlying Index, but which NTI believes will help the Fund track its Underlying Index. 
The Underlying Index is created and sponsored by NTI, as the Index Provider. NTI also serves as the investment adviser to the Fund. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. 
The Fund may lend securities representing up to one-third of the value of the Fund’s total assets (including the value of the collateral received). 
The Fund is “non-diversified” under the Investment Company Act of 1940 (“1940 Act”), as amended, and may invest more of its assets in fewer issuers than “diversified” funds. 
From time to time the Fund may focus its investments (i.e., invest more than 15% of its total assets) in one or more particular countries or geographic regions. As of December 31, 2021, the Fund focused its investments in Japan. 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. 
Principal Risks
As with any investment, you could lose all or part of your investment in the Fund, and the Fund’s performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.
Equity Securities Risk is the risk that the values of the equity securities owned by the Fund may be more volatile and underperform other asset classes and the general securities markets.
Depositary Receipts Risk Foreign securities may trade in the form of depositary receipts. In addition to investment risks associated with the underlying issuer, depositary 
 

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FlexShares® Developed Markets ex-US Quality Low Volatility Index Fund (cont.)

receipts may expose the Fund to additional risks associated with non-uniform terms that apply to depositary receipt programs, including credit exposure to the depository bank and to the sponsors and other parties with whom the depository bank establishes the programs, currency, political, economic, market risks and the risks of an illiquid market for depositary receipts. Depositary receipts are generally subject to the same risks as the foreign securities that they evidence or into which they may be converted. Depositary receipts may not track the price of the underlying foreign securities on which they are based, may have limited voting rights, and may have a distribution subject to a fee charged by the depository. As a result, equity shares of the underlying issuer may trade at a discount or premium to the market price of the depositary receipts. 
Low Volatility Risk is the risk that although the Underlying Index is designed to have overall volatility that is lower than that of the Parent Index, there is no guarantee it will be successful. Securities or other assets in the Fund’s portfolio may be subject to price volatility and the prices may not be any less volatile than the market as a whole and could be more volatile. The market prices of the securities or other assets in the Fund’s portfolio may fluctuate, sometimes rapidly and unpredictably. The Fund will continue to seek to track the Underlying Index even if the Underlying Index does not have lower overall volatility than the Parent Index. There is also the risk that the Fund may experience volatility greater than that of the Parent Index as a result of tracking error. A portfolio of securities with greater volatility is generally considered to have a higher risk profile than a portfolio with lower volatility. 
Quality Factor Risk is the risk that the past performance of companies that have exhibited quality characteristics does not continue or the returns on securities issued by such companies may be less than returns from other styles of investing or the overall stock market. There may be periods when quality investing is out of favor and during which time the Fund's performance may suffer. 
Foreign Securities Risk is the risk that investing in foreign (non-U.S.) securities may result in the Fund experiencing more rapid and extreme changes in value than a fund that invests exclusively in securities of U.S. companies, due to less liquid markets and adverse economic, political, diplomatic, financial, and regulatory factors. Foreign govern- 
ments may impose limitations on foreigners’ ownership of interests in local issuers, restrictions on the ability to repatriate assets, and may also impose taxes. Any of these events could cause the value of the Fund’s investments to decline. Foreign banks, agents and securities depositories that hold the Fund’s foreign assets may be subject to little or no regulatory oversight over, or independent evaluation, of their operations. Additional costs associated with investments in foreign securities may include higher custodial fees than those applicable to domestic custodial arrangements and transaction costs of foreign currency conversions. Unless the Fund has hedged its foreign currency exposure, foreign securities risk also involves the risk of negative foreign currency rate fluctuations, which may cause the value of securities denominated in such foreign currency (or other instruments through which the Fund has exposure to foreign currencies) to decline in value. Currency exchange rates may fluctuate significantly over short periods of time. Currency hedging strategies, if used, are not always successful. For instance, forward foreign currency exchange contracts, if used by the Fund, could reduce performance if there are unanticipated changes in currency exchange rates. 
Geographic Risk is the risk that if a fund invests a significant portion of its total assets in certain issuers within the same country or geographic region, an economic, business or political development affecting that country or region may affect the value of the fund’s investments more than if the fund’s investments were not so concentrated in such country or region. 
Japan Investment Risk is the risk of investing in securities of Japanese issuers. The Japanese economy may be subject to considerable degrees of economic, political and social instability, which could negatively impact Japanese issuers. In recent times, Japan’s economic growth rate has remained low, and it may remain low in the future. In addition, Japan is subject to the risk of natural disasters, such as earthquakes, volcanic eruptions, typhoons and tsunamis, which could negatively affect the securities of Japanese companies held by the Fund. 
Market Risk is the risk that the value of the Fund’s investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude 
 

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FlexShares® Developed Markets ex-US Quality Low Volatility Index Fund (cont.)

of such changes in value cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, changes in interest rates, lack of liquidity in the bond or equity markets, or volatility in the equity markets. Market disruptions caused by local or regional events such as war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor sentiment could have a significant impact on the Fund and its investments and could result in the Fund’s shares trading at increased premiums or discounts to the Fund’s NAV. An outbreak of COVID-19, a respiratory disease caused by a novel coronavirus, has negatively affected the worldwide economy, the financial health of individual companies and the market in significant and unforeseen ways. The future impact of COVID-19 is currently unknown. The effects to public health, business and market conditions resulting from the COVID-19 pandemic may have a significant negative impact on the performance of the Fund’s investments. During periods of market disruption or other abnormal market conditions, the Fund’s exposure to the risks described elsewhere in this summary will likely increase. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track its Underlying Index or cause delays in the Underlying Index’s rebalancing or reconstitution schedule. During any such delay, it is possible that the Underlying Index and, in turn, the Fund will deviate from the Underlying Index’s stated methodology and therefore experience returns different than those that would have been achieved under a normal rebalancing or reconstitution schedule. Because the Fund is designed to maintain a high level of exposure to its Underlying Index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns. 
Market risk includes the risk that a particular style of investing, such as growth or value, may underperform the market generally. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global 
economies and financial markets. As a result, whether or not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected. Securities markets may experience great short-term volatility and may fall sharply at times. Different markets may behave differently from each other and a foreign market may move in the opposite direction from the U.S. market. 
Price changes may be temporary or last for extended periods. You could lose money over short periods due to fluctuation in the market prices of the Fund’s shares in response to market movements, and over longer periods during market downturns. 
Index Risk is the risk that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Underlying Index, even if that security generally is underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of an index. Additionally, the Fund rebalances and/or reconstitutes its portfolio in accordance with the Underlying Index, and, therefore, any changes to the Underlying Index’s rebalance and/or reconstitution schedule will result in corresponding changes to the Fund’s rebalance and/or reconstitution schedule. 
Tracking Error Risk is the risk that the Fund’s performance may vary substantially from the performance of the Underlying Index. The Fund’s performance may vary from the performance of the Underlying Index for a number of reasons including that the Fund incurs operating expenses that the Underlying Index does not and that the Fund accepts custom baskets. Tracking error risk may be higher for funds that track a foreign index, or an index that includes foreign securities, because regulatory and reporting requirements may differ from those in the U.S., and there is a heightened risk associated with limited availability and reliability of data used to construct the index. 
Sampling Risk is the risk that the Fund’s use of a representative sampling approach may result in increased tracking error because the securities selected for the Fund in the aggregate may vary from the investment profile of the Underlying Index. Additionally, the use of a representative sampling approach may result in the Fund holding a 
 

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FlexShares® Developed Markets ex-US Quality Low Volatility Index Fund (cont.)

smaller number of securities than the Underlying Index, and, as a result, an adverse development to an issuer of securities that the Fund holds could result in a greater decline in NAV than would be the case if the Fund held all of the securities in the Underlying Index. 
Authorized Participant Concentration Risk is the risk that the Fund may be adversely affected because it has a limited number of institutions that act as authorized participants (“Authorized Participants”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. This risk may be heightened because of its investments in non-U.S. securities. 
Calculation Methodology Risk is the risk that the Underlying Index’s calculation methodology or sources of information may not provide an accurate assessment of included issuers or correct valuation of securities, nor is the availability or timeliness of the production of the Index guaranteed. A security included in an Underlying Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently a Fund’s holdings may not exhibit returns consistent with that characteristic or exposure. Unusual market conditions may cause the provider of the Underlying Index to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Market Trading Risk is the risk that the Fund faces because its shares are listed on a securities exchange, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS MAY LEAD TO THE FUND’S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of its listing exchange, make trading in the shares inadvisable. The market prices 
of Fund shares will generally fluctuate in accordance with changes in its NAV, changes in the relative supply of, and demand for, Fund shares, and changes in the liquidity, or the perceived liquidity, of the Fund’s holdings. 
Derivatives Risk is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instruments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments. 
Futures Contracts Risk is the risk that there will be imperfect correlation between the change in market value of the Fund’s securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of NTI to correctly predict the direction of securities’ prices, interest rates, currency exchange rates and other economic factors, which may make the Fund’s returns more volatile or increase the risk of loss.
Options Contracts Risk Options contracts give the holder of the option the right to buy (or to sell) a position in a security or in a contract to the writer of the option, at a certain price. They are subject to correlation risk because there may be an imperfect correlation between the options and the securities markets that cause a given transaction to fail to achieve its objectives. The successful use of options depends on the investment adviser’s ability to predict correctly future price fluctuations and the degree of correlation between the options and securities markets. Exchanges can limit the number of positions that can be held or controlled by the Fund or the investment adviser, thus limiting the ability to implement the Fund’s strategies.
Forward Foreign Currency Contracts Risk is the risk that, if forward prices increase, a loss will occur to the extent that the agreed upon purchase price of the currency exceeds the price of the currency that was agreed to be sold. 
 

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FlexShares® Developed Markets ex-US Quality Low Volatility Index Fund (cont.)

Concentration Risk is the risk that, if the Fund is concentrated in a particular industry or group of industries, the Fund is likely to present more risks than a fund that is broadly diversified over several industries or groups of industries. Compared to the broad market, an individual industry may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock or regulatory changes. 
Mid Cap Stock Risk is the risk that stocks of mid-sized companies may be subject to more abrupt or erratic market movements than stocks of larger, more established companies, and may lack sufficient market liquidity. Mid-sized companies may have limited product lines or financial resources, and may be dependent upon a particular niche of the market, or may be dependent upon a small or inexperienced management group. Securities of smaller companies may trade less frequently and in lower volume than the securities of larger companies, which could lead to higher transaction costs. Generally the smaller the company size, the greater the risk. 
Non-Diversification Risk is the risk that because the Fund is non-diversified and may invest a larger percentage of its assets in the securities of fewer issuers than a diversified fund, the Fund’s performance will be more vulnerable to changes in the market value of a single issuer or group of issuers, and more susceptible to risks associated with a single economic, political or regulatory occurrence. 
Securities Lending Risk is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. 
It is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank. 
Fund Performance
The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund. Past performance (before and after taxes) does not necessarily indicate how 
the Fund will perform in the future. Updated information on the Fund’s performance results can be obtained by visiting flexshares.com
Calendar Year Total Returns
For the period shown in the bar chart above:
Best Quarter (6/30/2020): 10.34%
Worst Quarter (3/31/2020): -17.11%
Average Annual Total Returns
(for the periods ended December 31, 2021)
  One
Year
Since
Inception
of Fund
Inception
Date
of Fund
Before Taxes 9.13% 7.43% 7/15/2019
After Taxes on Distributions 8.43%
6.89%
After Taxes on Distributions and Sale of Shares 6.04% 5.78%
MSCI World ex-US Index* 12.62% 10.96%
Northern Trust Developed Markets ex-US Quality Low Volatility IndexSM* 9.18% 7.68%
* Reflects no deduction for fees, expenses or taxes.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement plans. After-tax returns may exceed the return before taxes due to an assumed tax benefit from realizing a capital loss on a sale of Fund shares.
Management
Investment Adviser and Portfolio Managers. NTI, a subsidiary of Northern Trust Corporation, serves as the Invest-
 

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FlexShares® Developed Markets ex-US Quality Low Volatility Index Fund (cont.)

ment Adviser of the Fund. Robert Anstine and Brendan Sullivan, each a Vice President of NTI, have served as Portfolio Managers of the Fund since its inception in July 2019. Volter Bagriy, a Vice President of NTI, has served as a Portfolio Manager of the Fund since March 2021.
Purchase and Sale of Fund Shares
The Fund is an exchange-traded fund (commonly referred to as an “ETF”). The Fund’s shares may be issued and redeemed only by certain large institutions, referred to as “Authorized Participants,” that enter into agreements with the Fund’s principal underwriter. Retail investors may acquire and sell Fund shares in the secondary market through a broker-dealer. The price of Fund shares is based on market price, and because ETF shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the Fund (bid) and the lowest price a seller is willing to accept for shares of the Fund (ask) when buying or selling shares in the secondary market (“the bid-ask spread”). Recent information, including information about the Fund’s NAV, market price, premiums and discounts, and bid-ask spreads, is included on the Fund’s website at flexshares.com.
Tax Information
The Fund’s distributions are generally taxable to you as ordinary income, qualified dividends, capital gains, or a combination of the three, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account. Distributions may be taxable upon withdrawal from tax-advantaged accounts.
Payments to Brokers-Dealers and Other Financial Intermediaries
If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), NTI and its related companies may pay the intermediary for activities related to the marketing and promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

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FlexShares® Emerging Markets Quality Low Volatility Index Fund

Investment Objective
The Fund seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the Northern Trust Emerging Markets Quality Low Volatility IndexSM (the “Underlying Index”).
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Under the Fund’s Investment Advisory Agreement, the Fund is responsible for the following expenses: interest expenses, brokerage commissions and other trading expenses, fees and expenses of the independent trustees and their independent legal counsel, taxes and other extraordinary costs such as litigation and other expenses not incurred in the ordinary course of business. You will also incur usual and customary brokerage commissions and fees to financial intermediaries when buying or selling shares of the Fund in the secondary market, which are not reflected in the example that follows:
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fees 0.40%
Distribution (12b-1) Fees 0.00%
Other Expenses 0.01%
Total Annual Fund Operating Expenses 0.41%
Expense Reimbursement(1) -0.01%
Total Annual Fund Operating Expenses After Expense Reimbursement 0.40%
(1) Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than Acquired Fund Fees and Expenses) to the extent the “Total Annual Fund Operating Expenses” exceed 0.40%. This contractual limitation may not be terminated before March 1, 2023 without the approval of the Fund’s Board of Trustees. The Fund’s Board of Trustees may terminate the contractual agreement at any time if it determines that it is in the best interest of the Fund and its shareholders.
Example
The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5%
return each year and that the Fund’s operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year $41
3 Years $131
5 Years $229
10 Years $517
Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. Portfolio turnover may vary from year to year, as well as within a year. During the most recent fiscal year, the Fund’s portfolio turnover rate was 54% of the average value of its portfolio.
Principal Investment Strategies
The Underlying Index is designed to reflect the performance of a selection of companies that, in aggregate, possess lower overall absolute volatility characteristics relative to a broad universe of securities domiciled in emerging market countries, (the “Parent Index”). The Parent Index is a subset of the Northern Trust Global Index, limited to those securities domiciled in emerging markets and designated as large- and mid-capitalization companies by Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”), acting in its capacity as the index provider (the “Index Provider”). In addition, the Underlying Index is designed to select companies from the Parent Index that exhibit financial strength, stability and enhanced risk-return characteristics, which NTI believes can provide equity-market participation while seeking to protect against downside risks during certain market environments.
To derive the Underlying Index, the Index Provider ranks all constituents of the Parent Index using a Northern Trust proprietary quality factor. This factor is a quantitative ranking based on: (a) management expertise (e.g. corporate finance activities); (b) profitability (e.g. reliability and 
 

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FlexShares® Emerging Markets Quality Low Volatility Index Fund (cont.)

sustainability of financial performance); and (c) cash flow (e.g. cash flow generation). The Index Provider then excludes the lowest quintile of constituents ranked according to the quality factor and uses an optimization process to select and weight eligible securities in order to (a) seek to reduce overall portfolio volatility and (b) maximize the overall quality factor relative to the Parent Index. The optimization also includes sector, industry group, country, single-security weight, historical beta (i.e. market sensitivity, relative to the Parent Index) and turnover constraints so that these characteristics of the Underlying Index vary within acceptable bands relative to the Parent Index. 
As of December 31, 2021, the Underlying Index was comprised of 154 constituent securities with market capitalizations ranging from $2 billion to $576 billion. The Underlying Index is governed by published, objective rules for security selection, exclusion, weighting, rebalancing and adjustments for corporate actions and is reconstituted quarterly. The Fund generally reconstitutes its portfolio in accordance with the Underlying Index. 
NTI uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. 
NTI uses a representative sampling strategy to manage the Fund. “Representative sampling” is investing in a representative sample of securities that collectively has an investment profile similar to the Underlying Index. The Fund may or may not hold all of the securities that are included in the Underlying Index. The Fund reserves the right to invest in substantially all of the securities in its Underlying Index in approximately the same proportions (i.e., replication) if NTI determines that it is in the best interest of the Fund. 
Under normal circumstances, the Fund will invest at least 80% of its total assets (exclusive of collateral held from securities lending) in the securities of the Underlying Index and in American Depositary Receipts (“ADRs”) and Global Depositary Receipts (“GDRs”) (collectively “Depositary Receipts”) based on the securities in the Underlying Index. The Fund may also invest up to 20% of its assets in cash and cash equivalents, including shares of money market funds advised by NTI or its affiliates, futures contracts, 
options on futures contracts and forward currency contracts, as well as securities not included in the Underlying Index, but which NTI believes will help the Fund track its Underlying Index. 
The Underlying Index is created and sponsored by NTI, as the Index Provider. NTI also serves as the investment adviser to the Fund. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. 
The Fund may lend securities representing up to one-third of the value of the Fund’s total assets (including the value of the collateral received). 
The Fund is “non-diversified” under the Investment Company Act of 1940 (“1940 Act”), as amended, and may invest more of its assets in fewer issuers than “diversified” funds. 
From time to time the Fund may focus its investments (i.e., invest more than 15% of its total assets) in one or more particular countries or geographic regions. As of December 31, 2021, the Fund focused its investments in China and Taiwan. 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. 
Principal Risks
As with any investment, you could lose all or part of your investment in the Fund, and the Fund’s performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.
Equity Securities Risk is the risk that the values of the equity securities owned by the Fund may be more volatile and underperform other asset classes and the general securities markets. 
 

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FlexShares® Emerging Markets Quality Low Volatility Index Fund (cont.)

Mid Cap Stock Risk is the risk that stocks of mid-sized companies may be subject to more abrupt or erratic market movements than stocks of larger, more established companies, and may lack sufficient market liquidity. Mid-sized companies may have limited product lines or financial resources, and may be dependent upon a particular niche of the market, or may be dependent upon a small or inexperienced management group. Securities of smaller companies may trade less frequently and in lower volume than the securities of larger companies, which could lead to higher transaction costs. Generally the smaller the company size, the greater the risk. 
Depositary Receipts Risk Foreign securities may trade in the form of depositary receipts. In addition to investment risks associated with the underlying issuer, depositary receipts may expose the Fund to additional risks associated with non-uniform terms that apply to depositary receipt programs, including credit exposure to the depository bank and to the sponsors and other parties with whom the depository bank establishes the programs, currency, political, economic, market risks and the risks of an illiquid market for depositary receipts. Depositary receipts are generally subject to the same risks as the foreign securities that they evidence or into which they may be converted. Depositary receipts may not track the price of the underlying foreign securities on which they are based, may have limited voting rights, and may have a distribution subject to a fee charged by the depository. As a result, equity shares of the underlying issuer may trade at a discount or premium to the market price of the depositary receipts. 
Low Volatility Risk is the risk that although the Underlying Index is designed to have overall volatility that is lower than that of the Parent Index, there is no guarantee it will be successful. Securities or other assets in the Fund’s portfolio may be subject to price volatility and the prices may not be any less volatile than the market as a whole and could be more volatile. The market prices of the securities or other assets in the Fund’s portfolio may fluctuate, sometimes rapidly and unpredictably. The Fund will continue to seek to track the Underlying Index even if the Underlying Index does not have lower overall volatility than the Parent Index. There is also the risk that the Fund may experience volatility greater than that of the Parent Index as a result of tracking error. A portfolio of securities with greater volatility is generally considered to have a higher risk profile than a portfolio with lower volatility. 
Quality Factor Risk is the risk that the past performance of companies that have exhibited quality characteristics does not continue or the returns on securities issued by such companies may be less than returns from other styles of investing or the overall stock market. There may be periods when quality investing is out of favor and during which time the Fund's performance may suffer. 
Emerging Markets Risk is the risk that emerging markets are generally subject to greater market volatility, political, social and economic instability, uncertain trading markets and more governmental limitations on foreign investments than more developed markets. In addition, companies operating in emerging markets may be subject to lower trading volumes and greater price volatility than companies in more developed markets. Emerging market economies may be based on only a few industries, may be highly vulnerable to changes in local and global trade conditions, and may suffer from extreme and volatile debt burdens or inflation rates. Companies in emerging market countries generally may be subject to less stringent regulatory, disclosure, financial reporting, accounting, auditing and recordkeeping standards than companies in more developed countries. As a result, information, including financial information, about such companies may be less available and reliable, which can impede the Fund’s ability to evaluate such companies. Securities law and the enforcement of systems of taxation in many emerging market countries may change quickly and unpredictably, and the ability to bring and enforce actions (including bankruptcy, confiscatory taxation, expropriation, nationalization of a company’s assets, restrictions on foreign ownership of local companies, restrictions on withdrawing assets from the country, protectionist measures and practices such as share blocking), or to obtain information needed to pursue or enforce such actions, may be limited. Investments in emerging market securities may be subject to additional transaction costs, delays in settlement procedures, unexpected market closures, and lack of timely information. 
Foreign Securities Risk is the risk that investing in foreign (non-U.S.) securities may result in the Fund experiencing more rapid and extreme changes in value than a fund that invests exclusively in securities of U.S. companies, due to less liquid markets and adverse economic, political, diplomatic, financial, and regulatory factors. Foreign governments may impose limitations on foreigners’ ownership of 
 

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FlexShares® Emerging Markets Quality Low Volatility Index Fund (cont.)

interests in local issuers, restrictions on the ability to repatriate assets, and may also impose taxes. Any of these events could cause the value of the Fund’s investments to decline. Foreign banks, agents and securities depositories that hold the Fund’s foreign assets may be subject to little or no regulatory oversight over, or independent evaluation, of their operations. Additional costs associated with investments in foreign securities may include higher custodial fees than those applicable to domestic custodial arrangements and transaction costs of foreign currency conversions. Unless the Fund has hedged its foreign currency exposure, foreign securities risk also involves the risk of negative foreign currency rate fluctuations, which may cause the value of securities denominated in such foreign currency (or other instruments through which the Fund has exposure to foreign currencies) to decline in value. Currency exchange rates may fluctuate significantly over short periods of time. Currency hedging strategies, if used, are not always successful. For instance, forward foreign currency exchange contracts, if used by the Fund, could reduce performance if there are unanticipated changes in currency exchange rates. 
Geographic Risk is the risk that if a fund invests a significant portion of its total assets in certain issuers within the same country or geographic region, an economic, business or political development affecting that country or region may affect the value of the fund’s investments more than if the fund’s investments were not so concentrated in such country or region. 
China Investment Risk is the risk associated with investments in companies located or operating in China, such as nationalization, expropriation, or confiscation of property; alteration or discontinuation of economic reforms; and considerable degrees of economic, political and social instability. Investors in Chinese markets generally experience difficulties in obtaining information necessary for investigations into and/or litigation against Chinese companies, as well as in obtaining and/or enforcing judgements due to a lack of publicly available information; and there are generally limited legal remedies for shareholders. Internal social unrest or confrontations with other neighboring countries, including military conflicts, may disrupt economic development in China and result in a greater risk of currency fluctuations, currency convertibility, interest rate fluctuations and higher rates of inflation. 
  Export growth continues to be a major driver of China’s rapid economic growth. As a result, a reduction in spending on Chinese products and services, the institution of additional tariffs or other trade barriers, including as a result of heightened trade tensions between China and the U.S., or a downturn in any of the economies of China’s key trading partners may have an adverse impact on the Chinese economy. The inability of the Public Company Accounting Oversight Board (“PCAOB”) to inspect audit work papers and practices of PCAOB-registered accounting firms in China with respect to their audit work of U.S. reporting companies may impose significant additional risks associated with investments in China. Certain securities issued by companies located or operating in China, such as China A-shares, are subject to trading restrictions and suspensions, quota limitations and sudden changes in those limitations, and operational, clearing and settlement risks.
Taiwan Investment Risk is the risk of investing in securities of Taiwanese issuers. Specifically, Taiwan’s geographic proximity and history of political contention with China have resulted in ongoing tensions between the two countries, which may materially affect the Taiwanese economy and its securities market. Investments in securities of Taiwanese companies are subject to Taiwan’s heavy dependence on exports. Reductions in spending on Taiwanese products and services, labor shortages, institution of tariffs or other trade barriers, or a downturn in any of the economies of Taiwan’s key trading partners, including the United States, may have an adverse impact on the Taiwanese economy and the values of Taiwanese companies. 
Market Risk is the risk that the value of the Fund’s investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude of such changes in value cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, changes in interest rates, lack of liquidity in the bond or equity markets, or volatility in the equity markets. Market disruptions caused by local or regional events such as war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor 
 

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FlexShares® Emerging Markets Quality Low Volatility Index Fund (cont.)

sentiment could have a significant impact on the Fund and its investments and could result in the Fund’s shares trading at increased premiums or discounts to the Fund’s NAV. An outbreak of COVID-19, a respiratory disease caused by a novel coronavirus, has negatively affected the worldwide economy, the financial health of individual companies and the market in significant and unforeseen ways. The future impact of COVID-19 is currently unknown. The effects to public health, business and market conditions resulting from the COVID-19 pandemic may have a significant negative impact on the performance of the Fund’s investments. During periods of market disruption or other abnormal market conditions, the Fund’s exposure to the risks described elsewhere in this summary will likely increase. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track its Underlying Index or cause delays in the Underlying Index’s rebalancing or reconstitution schedule. During any such delay, it is possible that the Underlying Index and, in turn, the Fund will deviate from the Underlying Index’s stated methodology and therefore experience returns different than those that would have been achieved under a normal rebalancing or reconstitution schedule. Because the Fund is designed to maintain a high level of exposure to its Underlying Index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns. 
Market risk includes the risk that a particular style of investing, such as growth or value, may underperform the market generally. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global economies and financial markets. As a result, whether or not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected. Securities markets may experience great short-term volatility and may fall sharply at times. Different markets may behave differently from each other and a foreign market may move in the opposite direction from the U.S. market. 
Price changes may be temporary or last for extended periods. You could lose money over short periods due to fluc- 
tuation in the market prices of the Fund’s shares in response to market movements, and over longer periods during market downturns. 
Index Risk is the risk that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Underlying Index, even if that security generally is underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of an index. Additionally, the Fund rebalances and/or reconstitutes its portfolio in accordance with the Underlying Index, and, therefore, any changes to the Underlying Index’s rebalance and/or reconstitution schedule will result in corresponding changes to the Fund’s rebalance and/or reconstitution schedule. 
Tracking Error Risk is the risk that the Fund’s performance may vary substantially from the performance of the Underlying Index. The Fund’s performance may vary from the performance of the Underlying Index for a number of reasons including that the Fund incurs operating expenses that the Underlying Index does not and that the Fund accepts custom baskets. Tracking error risk may be higher for funds that track a foreign index, or an index that includes foreign securities, because regulatory and reporting requirements may differ from those in the U.S., and there is a heightened risk associated with limited availability and reliability of data used to construct the index. 
Sampling Risk is the risk that the Fund’s use of a representative sampling approach may result in increased tracking error because the securities selected for the Fund in the aggregate may vary from the investment profile of the Underlying Index. Additionally, the use of a representative sampling approach may result in the Fund holding a smaller number of securities than the Underlying Index, and, as a result, an adverse development to an issuer of securities that the Fund holds could result in a greater decline in NAV than would be the case if the Fund held all of the securities in the Underlying Index. 
Authorized Participant Concentration Risk is the risk that the Fund may be adversely affected because it has a limited number of institutions that act as authorized participants (“Authorized Participants”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund and none of those Authorized Par- 
 

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FlexShares® Emerging Markets Quality Low Volatility Index Fund (cont.)

ticipants is obligated to engage in creation and/or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. This risk may be heightened because of its investments in non-U.S. securities. 
Calculation Methodology Risk is the risk that the Underlying Index’s calculation methodology or sources of information may not provide an accurate assessment of included issuers or correct valuation of securities, nor is the availability or timeliness of the production of the Index guaranteed. A security included in an Underlying Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently a Fund’s holdings may not exhibit returns consistent with that characteristic or exposure. Unusual market conditions may cause the provider of the Underlying Index to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Market Trading Risk is the risk that the Fund faces because its shares are listed on a securities exchange, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS MAY LEAD TO THE FUND’S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of its listing exchange, make trading in the shares inadvisable. The market prices of Fund shares will generally fluctuate in accordance with changes in its NAV, changes in the relative supply of, and demand for, Fund shares, and changes in the liquidity, or the perceived liquidity, of the Fund’s holdings. 
Derivatives Risk is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instruments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the 
value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments. 
Futures Contracts Risk is the risk that there will be imperfect correlation between the change in market value of the Fund’s securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of NTI to correctly predict the direction of securities’ prices, interest rates, currency exchange rates and other economic factors, which may make the Fund’s returns more volatile or increase the risk of loss.
Options Contracts Risk Options contracts give the holder of the option the right to buy (or to sell) a position in a security or in a contract to the writer of the option, at a certain price. They are subject to correlation risk because there may be an imperfect correlation between the options and the securities markets that cause a given transaction to fail to achieve its objectives. The successful use of options depends on the investment adviser’s ability to predict correctly future price fluctuations and the degree of correlation between the options and securities markets. Exchanges can limit the number of positions that can be held or controlled by the Fund or the investment adviser, thus limiting the ability to implement the Fund’s strategies.
Forward Foreign Currency Contracts Risk is the risk that, if forward prices increase, a loss will occur to the extent that the agreed upon purchase price of the currency exceeds the price of the currency that was agreed to be sold. 
Concentration Risk is the risk that, if the Fund is concentrated in a particular industry or group of industries, the Fund is likely to present more risks than a fund that is broadly diversified over several industries or groups of industries. Compared to the broad market, an individual industry may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock or regulatory changes. 
 

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FlexShares® Emerging Markets Quality Low Volatility Index Fund (cont.)

Non-Diversification Risk is the risk that because the Fund is non-diversified and may invest a larger percentage of its assets in the securities of fewer issuers than a diversified fund, the Fund’s performance will be more vulnerable to changes in the market value of a single issuer or group of issuers, and more susceptible to risks associated with a single economic, political or regulatory occurrence. 
Securities Lending Risk is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. 
Valuation Risk is the risk that the sale price the Fund could receive for a portfolio security may differ from the Fund’s valuation of the security, particularly for securities that trade in low volume or volatile markets or that are valued using a fair value methodology. In addition, the value of the securities in the Fund’s portfolio may change on days when shareholders will not be able to purchase or sell the Fund’s shares. 
It is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank. 
Fund Performance
The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated information on the Fund’s performance results can be obtained by visiting flexshares.com.
Calendar Year Total Returns
For the period shown in the bar chart above:
Best Quarter (6/30/2020): 12.19%
Worst Quarter (3/31/2020): -21.67%
Average Annual Total Returns
(for the periods ended December 31, 2021)
  One
Year
Since
Inception
of Fund
Inception
Date
of Fund
Before Taxes 1.28% 4.23% 7/15/2019
After Taxes on Distributions 0.84%
3.80%
After Taxes on Distributions and Sale of Shares 1.36% 3.36%
MSCI Emerging Markets Index* -2.54% 8.69%
Northern Trust Emerging Markets Quality Low Volatility IndexSM* 2.55% 5.05%
* Reflects no deduction for fees, expenses or taxes.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement plans. After-tax returns may exceed the return before taxes due to an assumed tax benefit from realizing a capital loss on a sale of Fund shares.
Management
Investment Adviser and Portfolio Managers. NTI, a subsidiary of Northern Trust Corporation, serves as the Investment Adviser of the Fund. Robert Anstine and Brendan Sullivan, each a Vice President of NTI, have served as Port-
 

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FlexShares® Emerging Markets Quality Low Volatility Index Fund (cont.)

folio Managers of the Fund since its inception in July 2019. Volter Bagriy, a Vice President of NTI, has served as a Portfolio Manager of the Fund since March 2021.
Purchase and Sale of Fund Shares
The Fund is an exchange-traded fund (commonly referred to as an “ETF”). The Fund’s shares may be issued and redeemed only by certain large institutions, referred to as “Authorized Participants,” that enter into agreements with the Fund’s principal underwriter. Retail investors may acquire and sell Fund shares in the secondary market through a broker-dealer. The price of Fund shares is based on market price, and because ETF shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the Fund (bid) and the lowest price a seller is willing to accept for shares of the Fund (ask) when buying or selling shares in the secondary market (“the bid-ask spread”). Recent information, including information about the Fund’s NAV, market price, premiums and discounts, and bid-ask spreads, is included on the Fund’s website at flexshares.com.
Tax Information
The Fund’s distributions are generally taxable to you as ordinary income, qualified dividends, capital gains, or a combination of the three, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account. Distributions may be taxable upon withdrawal from tax-advantaged accounts.
Payments to Brokers-Dealers and Other Financial Intermediaries
If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), NTI and its related companies may pay the intermediary for activities related to the marketing and promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

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FlexShares® Morningstar US Market Factor Tilt Index Fund

Investment Objective
The Fund seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the Morningstar® US Market Factor Tilt IndexSM (the “Underlying Index”).
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Under the Fund’s Investment Advisory Agreement, the Fund is responsible for the following expenses: interest expenses, brokerage commissions and other trading expenses, fees and expenses of the independent trustees and their independent legal counsel, taxes and other extraordinary costs such as litigation and other expenses not incurred in the ordinary course of business. You will also incur usual and customary brokerage commissions and fees to financial intermediaries when buying or selling shares of the Fund in the secondary market, which are not reflected in the example that follows:
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fees 0.25%
Distribution (12b-1) Fees 0.00%
Other Expenses 0.01%
Total Annual Fund Operating Expenses 0.26%
Expense Reimbursement(1) -0.01%
Total Annual Fund Operating Expenses After Expense Reimbursement 0.25%
(1) Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than Acquired Fund Fees and Expenses) to the extent the “Total Annual Fund Operating Expenses” exceed 0.25%. This contractual limitation may not be terminated before March 1, 2023 without the approval of the Fund’s Board of Trustees. The Fund’s Board of Trustees may terminate the contractual agreement at any time if it determines that it is in the best interest of the Fund and its shareholders.
Example
The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5%
return each year and that the Fund’s operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year $26
3 Years $83
5 Years $145
10 Years $330
Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. Portfolio turnover may vary from year to year, as well as within a year. During the most recent fiscal year, the Fund’s portfolio turnover rate was 24% of the average value of its portfolio.
Principal Investment Strategies
The Underlying Index is designed to reflect the performance of a selection of companies that, in aggregate, possess greater exposure to size and value factors relative to the Morningstar US Market Index (the “Parent Index”), a float-adjusted market-capitalization weighted index of U.S.-incorporated large-, mid-, small- and micro-capitalization companies. The Underlying Index seeks to achieve increased exposures to size and value factors, or a “factor tilt”, by adjusting the Parent Index’s constituent weights to achieve a slightly greater weight on companies with smaller market capitalizations or lower valuations, as determined by Morningstar, Inc. (the “Index Provider”) pursuant to its index methodology. The Underlying Index is designed to include companies with enhanced risk-return characteristics relative to the broader U.S. equity market by featuring size and value risk premiums, which Northern Trust Investments, Inc. (“NTI” or “Investment Adviser”) believes have been historically demonstrated over a full market cycle. As of December 31, 2021, the Underlying Index was comprised of 2,618 issues with market capitalizations ranging from $179 million to $2.9 trillion. The Underlying Index is governed by published, objective rules 
 

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FlexShares® Morningstar US Market Factor Tilt Index Fund (cont.)

for security selection, exclusion, rebalancing and adjustments for corporate actions. It is reconstituted on a semi-annual basis and is rebalanced quarterly. The Fund generally reconstitutes and rebalances its portfolio in accordance with the Underlying Index. 
NTI uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. 
NTI uses a representative sampling strategy to manage the Fund. “Representative sampling” is investing in a representative sample of securities that collectively has an investment profile similar to the Underlying Index. The Fund may or may not hold all of the securities that are included in the Underlying Index. The Fund reserves the right to invest in substantially all of the securities in its Underlying Index in approximately the same proportions (i.e., replication) if NTI determines that it is in the best interest of the Fund. 
Under normal circumstances, the Fund will invest at least 80% of its total assets (exclusive of collateral held from securities lending) in the securities of the Underlying Index. The Fund may also invest up to 20% of its assets in cash and cash equivalents, including shares of money market funds advised by NTI or its affiliates, futures contracts and options on futures contracts, as well as securities not included in the Underlying Index, but which NTI believes will help the Fund track its Underlying Index. 
The Underlying Index is sponsored by the Index Provider, an organization that is independent of the Fund and NTI. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. 
The Fund may lend securities representing up to one-third of the value of the Fund’s total assets (including the value of the collateral received). 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. 
Principal Risks
As with any investment, you could lose all or part of your investment in the Fund, and the Fund’s performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.
Equity Securities Risk is the risk that the values of the equity securities owned by the Fund may be more volatile and underperform other asset classes and the general securities markets.
Concentration Risk is the risk that, if the Fund is concentrated in a particular industry or group of industries, the Fund is likely to present more risks than a fund that is broadly diversified over several industries or groups of industries. Compared to the broad market, an individual industry may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock or regulatory changes.
Market Risk is the risk that the value of the Fund’s investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude of such changes in value cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, changes in interest rates, lack of liquidity in the bond or equity markets, or volatility in the equity markets. Market disruptions caused by local or regional events such as war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor sentiment could have a significant impact on the Fund and its investments and could result in the Fund’s shares trading at increased premiums or discounts to the Fund’s NAV. An outbreak of COVID-19, a respiratory disease caused by a novel coronavirus, has negatively affected the worldwide economy, the financial health of individual companies and 
 

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FlexShares® Morningstar US Market Factor Tilt Index Fund (cont.)

the market in significant and unforeseen ways. The future impact of COVID-19 is currently unknown. The effects to public health, business and market conditions resulting from the COVID-19 pandemic may have a significant negative impact on the performance of the Fund’s investments. During periods of market disruption or other abnormal market conditions, the Fund’s exposure to the risks described elsewhere in this summary will likely increase. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track its Underlying Index or cause delays in the Underlying Index’s rebalancing or reconstitution schedule. During any such delay, it is possible that the Underlying Index and, in turn, the Fund will deviate from the Underlying Index’s stated methodology and therefore experience returns different than those that would have been achieved under a normal rebalancing or reconstitution schedule. Because the Fund is designed to maintain a high level of exposure to its Underlying Index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns. 
Market risk includes the risk that a particular style of investing, such as growth or value, may underperform the market generally. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global economies and financial markets. As a result, whether or not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected. Securities markets may experience great short-term volatility and may fall sharply at times. Different markets may behave differently from each other and a foreign market may move in the opposite direction from the U.S. market. 
Price changes may be temporary or last for extended periods. You could lose money over short periods due to fluctuation in the market prices of the Fund’s shares in response to market movements, and over longer periods during market downturns. 
Index Risk is the risk that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Underlying Index, even if 
that security generally is underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of an index. Additionally, the Fund rebalances and/or reconstitutes its portfolio in accordance with the Underlying Index, and, therefore, any changes to the Underlying Index’s rebalance and/or reconstitution schedule will result in corresponding changes to the Fund’s rebalance and/or reconstitution schedule. 
Tracking Error Risk is the risk that the Fund’s performance may vary substantially from the performance of the Underlying Index. The Fund’s performance may vary from the performance of the Underlying Index for a number of reasons including that the Fund incurs operating expenses that the Underlying Index does not and that the Fund accepts custom baskets. 
Sampling Risk is the risk that the Fund’s use of a representative sampling approach may result in increased tracking error because the securities selected for the Fund in the aggregate may vary from the investment profile of the Underlying Index. Additionally, the use of a representative sampling approach may result in the Fund holding a smaller number of securities than the Underlying Index, and, as a result, an adverse development to an issuer of securities that the Fund holds could result in a greater decline in NAV than would be the case if the Fund held all of the securities in the Underlying Index. 
Value Investing Risk is the risk that the Fund’s investment in companies whose securities are believed to be undervalued, relative to their underlying profitability, will not appreciate in value as anticipated. 
Mid and Small Cap Stock Risk is the risk that stocks of mid-sized and smaller companies may be more volatile than stocks of larger, more established companies, and may lack sufficient market liquidity. Mid-sized and small companies may have limited product lines or financial resources, may be dependent upon a particular niche of the market, or may be dependent upon a small or inexperienced management group. Smaller companies may also include micro-capitalization companies. Securities of smaller companies may trade less frequently and in lower volume than the securities of larger companies, which could lead to higher transaction costs. Generally the smaller the company size, the greater the risk. 
 

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FlexShares® Morningstar US Market Factor Tilt Index Fund (cont.)

Authorized Participant Concentration Risk is the risk that the Fund may be adversely affected because it has a limited number of institutions that act as authorized participants (“Authorized Participants”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. 
Calculation Methodology Risk is the risk that the Underlying Index’s calculation methodology or sources of information may not provide an accurate assessment of included issuers or correct valuation of securities, nor is the availability or timeliness of the production of the Index guaranteed. A security included in an Underlying Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently a Fund's holdings may not exhibit returns consistent with that characteristic or exposure. Unusual market conditions may cause the provider of the Underlying Index to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Market Trading Risk is the risk that the Fund faces because its shares are listed on a securities exchange, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS MAY LEAD TO THE FUND’S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of its listing exchange, make trading in the shares inadvisable. The market prices of Fund shares will generally fluctuate in accordance with changes in its NAV, changes in the relative supply of, and demand for, Fund shares, and changes in the liquidity, or the perceived liquidity, of the Fund’s holdings. 
Derivatives Risk is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instru- 
ments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments. 
Futures Contracts Risk is the risk that there will be imperfect correlation between the change in market value of the Fund’s securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of NTI to correctly predict the direction of securities’ prices, interest rates, currency exchange rates and other economic factors, which may make the Fund’s returns more volatile or increase the risk of loss.
Options Contracts Risk Options contracts give the holder of the option the right to buy (or to sell) a position in a security or in a contract to the writer of the option, at a certain price. They are subject to correlation risk because there may be an imperfect correlation between the options and the securities markets that cause a given transaction to fail to achieve its objectives. The successful use of options depends on the investment adviser’s ability to predict correctly future price fluctuations and the degree of correlation between the options and securities markets. Exchanges can limit the number of positions that can be held or controlled by the Fund or the investment adviser, thus limiting the ability to implement the Fund’s strategies. 
Securities Lending Risk is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. 
It is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit 
 

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FlexShares® Morningstar US Market Factor Tilt Index Fund (cont.)

Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank.
Fund Performance
The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated information on the Fund’s performance results can be obtained by visiting flexshares.com.
Calendar Year Total Returns
For the periods in the bar chart above:
Best Quarter (6/30/2020): 22.45%
Worst Quarter (3/31/2020): -26.23%
Average Annual Total Returns
(for the periods ended December 31, 2021)
  One
Year
Five
Year
Ten
Year
Since
Inception
of Fund
Inception
Date
of Fund
Before Taxes 27.49% 15.53% 15.14% 15.12% 9/16/2011
After Taxes on Distributions 27.10%
15.04%
14.70%
14.69%
After Taxes on Distributions and Sale of Shares 16.50% 12.38% 12.68% 12.69%
Morningstar® US Market Factor Tilt IndexSM* 27.71% 15.63% 15.31% 15.29%
* Reflects no deduction for fees, expenses or taxes.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not
reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement plans. After-tax returns may exceed the return before taxes due to an assumed tax benefit from realizing a capital loss on a sale of Fund shares.
Management
Investment Adviser and Portfolio Managers. NTI, a subsidiary of Northern Trust Corporation, serves as the Investment Adviser of the Fund. Robert Anstine, Brendan Sullivan and Alan Aung, each a Vice President of NTI, have served as Portfolio Managers of the Fund since October 2013, June 2016 and March 2021, respectively.
Purchase and Sale of Fund Shares
The Fund is an exchange-traded fund (commonly referred to as an “ETF”). The Fund’s shares may be issued and redeemed only by certain large institutions, referred to as “Authorized Participants,” that enter into agreements with the Fund’s principal underwriter. Retail investors may acquire and sell Fund shares in the secondary market through a broker-dealer. The price of Fund shares is based on market price, and because ETF shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the Fund (bid) and the lowest price a seller is willing to accept for shares of the Fund (ask) when buying or selling shares in the secondary market (“the bid-ask spread”). Recent information, including information about the Fund’s NAV, market price, premiums and discounts, and bid-ask spreads, is included on the Fund’s website at flexshares.com.
Tax Information
The Fund’s distributions are generally taxable to you as ordinary income, qualified dividends, capital gains, or a combination of the three, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account. Distributions may be taxable upon withdrawal from tax-advantaged accounts.
Payments to Brokers-Dealers and Other Financial Intermediaries
If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), NTI and its related
 

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FlexShares® Morningstar US Market Factor Tilt Index Fund (cont.)

companies may pay the intermediary for activities related to the marketing and promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

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FlexShares® Morningstar Developed
Markets ex-US Factor Tilt Index Fund

Investment Objective
The Fund seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the Morningstar® Developed Markets ex-US Factor Tilt IndexSM (the “Underlying Index”).
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Under the Fund’s Investment Advisory Agreement, the Fund is responsible for the following expenses: interest expenses, brokerage commissions and other trading expenses, fees and expenses of the independent trustees and their independent legal counsel, taxes and other extraordinary costs such as litigation and other expenses not incurred in the ordinary course of business. You will also incur usual and customary brokerage commissions and fees to financial intermediaries when buying or selling shares of the Fund in the secondary market, which are not reflected in the example that follows:
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fees 0.39%
Distribution (12b-1) Fees 0.00%
Other Expenses 0.01%
Total Annual Fund Operating Expenses 0.40%
Expense Reimbursement(1) -0.01%
Total Annual Fund Operating Expenses After Expense Reimbursement 0.39%
(1) Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than Acquired Fund Fees and Expenses) to the extent the “Total Annual Fund Operating Expenses” exceed 0.39%. This contractual limitation may not be terminated before March 1, 2023 without the approval of the Fund’s Board of Trustees. The Fund’s Board of Trustees may terminate the contractual agreement at any time if it determines that it is in the best interest of the Fund and its shareholders.
Example
The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5%
return each year and that the Fund’s operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year $40
3 Years $127
5 Years $223
10 Years $504
Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. Portfolio turnover may vary from year to year, as well as within a year. During the most recent fiscal year, the Fund’s portfolio turnover rate was 29% of the average value of its portfolio.
Principal Investment Strategies
The Underlying Index is designed to reflect the performance of a selection of companies that, in aggregate, possess greater exposure to size and value factors relative to the Morningstar Developed Markets ex-US Index (the “Parent Index”), a float-adjusted market-capitalization weighted index of companies incorporated in developed-market countries, excluding the U.S. The Underlying Index seeks to achieve increased exposures to size and value factors, or a “factor tilt”, by adjusting the Parent Index’s constituent weights to achieve a slightly greater weight on companies with smaller market capitalizations or lower valuations, as determined by Morningstar, Inc. (the “Index Provider”), pursuant to its index methodology. The Underlying Index is designed to include companies with enhanced risk-return characteristics relative to the broader developed international equity market by featuring size and value risk premiums, which Northern Trust Investments, Inc. (“NTI” or “Investment Adviser”) believes have been historically demonstrated over a full market cycle. As of December 31, 2021, the Underlying Index was comprised of 3,439 issues with market capitalizations ranging from $11.2 billion to $393.6 billion. The Underlying Index is governed by pub- 
 

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FlexShares® Morningstar Developed
Markets ex-US Factor Tilt Index Fund (cont.)

lished, objective rules for security selection, exclusion, rebalancing and adjustments for corporate actions and is reconstituted on a semi-annual basis and is rebalanced quarterly. The Fund generally reconstitutes and rebalances its portfolio in accordance with the Underlying Index. 
NTI uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. 
NTI uses a representative sampling strategy to manage the Fund. “Representative sampling” is investing in a representative sample of securities that collectively has an investment profile similar to the Underlying Index. The Fund may or may not hold all of the securities that are included in the Underlying Index. The Fund reserves the right to invest in substantially all of the securities in its Underlying Index in approximately the same proportions (i.e., replication) if NTI determines that it is in the best interest of the Fund. 
Under normal circumstances, the Fund will invest at least 80% of its total assets (exclusive of collateral held from securities lending) in the securities of the Underlying Index and in American Depositary Receipts (“ADRs”) and Global Depositary Receipts (“GDRs”) (collectively “Depositary Receipts”) based on the securities in the Underlying Index. The Fund may also invest up to 20% of its assets in cash and cash equivalents, including shares of money market funds advised by NTI or its affiliates, futures contracts, options on futures contracts and forward currency contracts, as well as securities not included in the Underlying Index, but which NTI believes will help the Fund track its Underlying Index. 
The Underlying Index is sponsored by the Index Provider, an organization that is independent of the Fund and NTI. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. 
The Fund may lend securities representing up to one-third of the value of the Fund’s total assets (including the value of the collateral received). 
From time to time the Fund may focus its investments (i.e., invest more than 15% of its total assets) in one or more particular countries or geographic regions. As of December 31, 2021, the Fund focused its investments in Japan. 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. 
Principal Risks
As with any investment, you could lose all or part of your investment in the Fund, and the Fund’s performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.
Equity Securities Risk is the risk that the values of the equity securities owned by the Fund may be more volatile and underperform other asset classes and the general securities markets.
Mid and Small Cap Stock Risk is the risk that stocks of mid-sized and smaller companies may be more volatile than stocks of larger, more established companies, and may lack sufficient market liquidity. Mid-sized and small companies may have limited product lines or financial resources, may be dependent upon a particular niche of the market, or may be dependent upon a small or inexperienced management group. Securities of smaller companies may trade less frequently and in lower volume than the securities of larger companies, which could lead to higher transaction costs. Generally the smaller the company size, the greater the risk.
Foreign Securities Risk is the risk that investing in foreign (non-U.S.) securities may result in the Fund experiencing more rapid and extreme changes in value than a fund that invests exclusively in securities of U.S. companies, due to less liquid markets and adverse economic, political, diplomatic, financial, and regulatory factors. Foreign governments may impose limitations on foreigners’ ownership of interests in local issuers, restrictions on the ability to repatriate assets, and may also impose taxes. Any of these events could cause the value of the Fund’s investments to 
 

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FlexShares® Morningstar Developed
Markets ex-US Factor Tilt Index Fund (cont.)

decline. Foreign banks, agents and securities depositories that hold the Fund’s foreign assets may be subject to little or no regulatory oversight over, or independent evaluation, of their operations. Additional costs associated with investments in foreign securities may include higher custodial fees than those applicable to domestic custodial arrangements and transaction costs of foreign currency conversions. Unless the Fund has hedged its foreign currency exposure, foreign securities risk also involves the risk of negative foreign currency rate fluctuations, which may cause the value of securities denominated in such foreign currency (or other instruments through which the Fund has exposure to foreign currencies) to decline in value. Currency exchange rates may fluctuate significantly over short periods of time. Currency hedging strategies, if used, are not always successful. For instance, forward foreign currency exchange contracts, if used by the Fund, could reduce performance if there are unanticipated changes in currency exchange rates. 
Geographic Risk is the risk that if a fund invests a significant portion of its total assets in certain issuers within the same country or geographic region, an economic, business or political development affecting that country or region may affect the value of the fund’s investments more than if the fund’s investments were not so concentrated in such country or region. 
Japan Investment Risk is the risk of investing in securities of Japanese issuers. The Japanese economy may be subject to considerable degrees of economic, political and social instability, which could negatively impact Japanese issuers. In recent times, Japan’s economic growth rate has remained low, and it may remain low in the future. In addition, Japan is subject to the risk of natural disasters, such as earthquakes, volcanic eruptions, typhoons and tsunamis, which could negatively affect the securities of Japanese companies held by the Fund. 
Concentration Risk is the risk that, if the Fund is concentrated in a particular industry or group of industries, the Fund is likely to present more risks than a fund that is broadly diversified over several industries or groups of industries. Compared to the broad market, an individual industry may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock or regulatory changes. 
Depositary Receipts Risk Foreign securities may trade in the form of depositary receipts. In addition to investment risks associated with the underlying issuer, depositary receipts may expose the Fund to additional risks associated with non-uniform terms that apply to depositary receipt programs, including credit exposure to the depository bank and to the sponsors and other parties with whom the depository bank establishes the programs, currency, political, economic, market risks and the risks of an illiquid market for depositary receipts. Depositary receipts are generally subject to the same risks as the foreign securities that they evidence or into which they may be converted. Depositary receipts may not track the price of the underlying foreign securities on which they are based, may have limited voting rights, and may have a distribution subject to a fee charged by the depository. As a result, equity shares of the underlying issuer may trade at a discount or premium to the market price of the depositary receipts. 
Market Risk is the risk that the value of the Fund’s investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude of such changes in value cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, changes in interest rates, lack of liquidity in the bond or equity markets, or volatility in the equity markets. Market disruptions caused by local or regional events such as war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor sentiment could have a significant impact on the Fund and its investments and could result in the Fund’s shares trading at increased premiums or discounts to the Fund’s NAV. An outbreak of COVID-19, a respiratory disease caused by a novel coronavirus, has negatively affected the worldwide economy, the financial health of individual companies and the market in significant and unforeseen ways. The future impact of COVID-19 is currently unknown. The effects to public health, business and market conditions resulting from the COVID-19 pandemic may have a significant negative impact on the performance of the Fund’s investments. During periods of market disruption or other abnormal market conditions, the Fund’s exposure to the 
 

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FlexShares® Morningstar Developed
Markets ex-US Factor Tilt Index Fund (cont.)

risks described elsewhere in this summary will likely increase. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track its Underlying Index or cause delays in the Underlying Index’s rebalancing or reconstitution schedule. During any such delay, it is possible that the Underlying Index and, in turn, the Fund will deviate from the Underlying Index’s stated methodology and therefore experience returns different than those that would have been achieved under a normal rebalancing or reconstitution schedule. Because the Fund is designed to maintain a high level of exposure to its Underlying Index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns. 
Market risk includes the risk that a particular style of investing, such as growth or value, may underperform the market generally. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global economies and financial markets. As a result, whether or not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected. Securities markets may experience great short-term volatility and may fall sharply at times. Different markets may behave differently from each other and a foreign market may move in the opposite direction from the U.S. market. 
Price changes may be temporary or last for extended periods. You could lose money over short periods due to fluctuation in the market prices of the Fund’s shares in response to market movements, and over longer periods during market downturns. 
Index Risk is the risk that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Underlying Index, even if that security generally is underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of an index. Additionally, the Fund rebalances and/or reconstitutes its portfolio in accordance with the Underlying Index, and, 
therefore, any changes to the Underlying Index’s rebalance and/or reconstitution schedule will result in corresponding changes to the Fund’s rebalance and/or reconstitution schedule. 
Tracking Error Risk is the risk that the Fund’s performance may vary substantially from the performance of the Underlying Index. The Fund’s performance may vary from the performance of the Underlying Index for a number of reasons including that the Fund incurs operating expenses that the Underlying Index does not and that the Fund accepts custom baskets. Tracking error risk may be higher for funds that track a foreign index, or an index that includes foreign securities, because regulatory and reporting requirements may differ from those in the U.S., and there is a heightened risk associated with limited availability and reliability of data used to construct the index. 
Sampling Risk is the risk that the Fund’s use of a representative sampling approach may result in increased tracking error because the securities selected for the Fund in the aggregate may vary from the investment profile of the Underlying Index. Additionally, the use of a representative sampling approach may result in the Fund holding a smaller number of securities than the Underlying Index, and, as a result, an adverse development to an issuer of securities that the Fund holds could result in a greater decline in NAV than would be the case if the Fund held all of the securities in the Underlying Index. 
Value Investing Risk is the risk that the Fund’s investment in companies whose securities are believed to be undervalued, relative to their underlying profitability, will not appreciate in value as anticipated. 
Authorized Participant Concentration Risk is the risk that the Fund may be adversely affected because it has a limited number of institutions that act as authorized participants (“Authorized Participants”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to 
 

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FlexShares® Morningstar Developed
Markets ex-US Factor Tilt Index Fund (cont.)

NAV and possibly face trading halts and/or delisting. This risk may be heightened because of its investments in non-U.S. securities. 
Calculation Methodology Risk is the risk that the Underlying Index’s calculation methodology or sources of information may not provide an accurate assessment of included issuers or correct valuation of securities, nor is the availability or timeliness of the production of the Index guaranteed. A security included in an Underlying Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently a Fund's holdings may not exhibit returns consistent with that characteristic or exposure. Unusual market conditions may cause the provider of the Underlying Index to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Market Trading Risk is the risk that the Fund faces because its shares are listed on a securities exchange, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS MAY LEAD TO THE FUND’S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of its listing exchange, make trading in the shares inadvisable. The market prices of Fund shares will generally fluctuate in accordance with changes in its NAV, changes in the relative supply of, and demand for, Fund shares, and changes in the liquidity, or the perceived liquidity, of the Fund’s holdings. 
Derivatives Risk is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instruments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments. 
Futures Contracts Risk is the risk that there will be imperfect correlation between the change in market value of the Fund’s securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of NTI to correctly predict the direction of securities’ prices, interest rates, currency exchange rates and other economic factors, which may make the Fund’s returns more volatile or increase the risk of loss.
Options Contracts Risk Options contracts give the holder of the option the right to buy (or to sell) a position in a security or in a contract to the writer of the option, at a certain price. They are subject to correlation risk because there may be an imperfect correlation between the options and the securities markets that cause a given transaction to fail to achieve its objectives. The successful use of options depends on the investment adviser’s ability to predict correctly future price fluctuations and the degree of correlation between the options and securities markets. Exchanges can limit the number of positions that can be held or controlled by the Fund or the investment adviser, thus limiting the ability to implement the Fund’s strategies.
Forward Foreign Currency Contracts Risk is the risk that, if forward prices increase, a loss will occur to the extent that the agreed upon purchase price of the currency exceeds the price of the currency that was agreed to be sold. 
Securities Lending Risk is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. 
It is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank. 
Fund Performance
The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indica- 
 

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FlexShares® Morningstar Developed
Markets ex-US Factor Tilt Index Fund (cont.)

tion of the risks of investing in the Fund. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated information on the Fund’s performance results can be obtained by visiting flexshares.com
Calendar Year Total Returns
For the periods in the bar chart above:
Best Quarter (12/31/2020): 18.86%
Worst Quarter (3/31/2020): -27.56%
Average Annual Total Returns
(for the periods ended December 31, 2021)
  One
Year
Five
Year
Since
Inception
of Fund
Inception
Date
of Fund
Before Taxes 12.26% 8.21% 6.87% 9/25/2012
After Taxes on Distributions 11.21%
7.39%
6.20%
After Taxes on Distributions and Sale of Shares 7.75% 6.32% 5.42%
Morningstar® Developed Markets ex-US Factor Tilt IndexSM* 12.37% 8.23% 6.97%
* Reflects no deduction for fees, expenses or taxes.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement plans. After-tax returns may exceed the return before taxes due to an assumed tax benefit from realizing a capital loss on a sale of Fund shares.
Management
Investment Adviser and Portfolio Managers. NTI, a subsidiary of Northern Trust Corporation, serves as the Investment Adviser of the Fund. Robert Anstine, Brendan Sullivan and Volter Bagriy, each a Vice President of NTI, have served as Portfolio Managers of the Fund since October 2013, June 2016 and March 2021, respectively.
Purchase and Sale of Fund Shares
The Fund is an exchange-traded fund (commonly referred to as an “ETF”). The Fund’s shares may be issued and redeemed only by certain large institutions, referred to as “Authorized Participants,” that enter into agreements with the Fund’s principal underwriter. Retail investors may acquire and sell Fund shares in the secondary market through a broker-dealer. The price of Fund shares is based on market price, and because ETF shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the Fund (bid) and the lowest price a seller is willing to accept for shares of the Fund (ask) when buying or selling shares in the secondary market (“the bid-ask spread”). Recent information, including information about the Fund’s NAV, market price, premiums and discounts, and bid-ask spreads, is included on the Fund’s website at flexshares.com.
Tax Information
The Fund’s distributions are generally taxable to you as ordinary income, qualified dividends, capital gains, or a combination of the three, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account. Distributions may be taxable upon withdrawal from tax-advantaged accounts.
Payments to Brokers-Dealers and Other Financial Intermediaries
If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), NTI and its related companies may pay the intermediary for activities related to the marketing and promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson
 

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FlexShares® Morningstar Developed
Markets ex-US Factor Tilt Index Fund (cont.)

to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

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Table of Contents

FlexShares® Morningstar Emerging
Markets Factor Tilt Index Fund

Investment Objective
The Fund seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the Morningstar® Emerging Markets Factor Tilt IndexSM (the “Underlying Index”).
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Under the Fund’s Investment Advisory Agreement, the Fund is responsible for the following expenses: interest expenses, brokerage commissions and other trading expenses, fees and expenses of the independent trustees and their independent legal counsel, taxes and other extraordinary costs such as litigation and other expenses not incurred in the ordinary course of business. You will also incur usual and customary brokerage commissions and fees to financial intermediaries when buying or selling shares of the Fund in the secondary market, which are not reflected in the example that follows:
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fees 0.59%
Distribution (12b-1) Fees 0.00%
Other Expenses 0.01%
Total Annual Fund Operating Expenses 0.60%
Expense Reimbursement(1) -0.01%
Total Annual Fund Operating Expenses After Expense Reimbursement 0.59%
(1) Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than Acquired Fund Fees and Expenses) to the extent the “Total Annual Fund Operating Expenses” exceed 0.59%. This contractual limitation may not be terminated before March 1, 2023 without the approval of the Fund’s Board of Trustees. The Fund’s Board of Trustees may terminate the contractual agreement at any time if it determines that it is in the best interest of the Fund and its shareholders.
Example
The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5%
return each year and that the Fund’s operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year $60
3 Years $191
5 Years $334
10 Years $749
Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. Portfolio turnover may vary from year to year, as well as within a year. During the most recent fiscal year, the Fund’s portfolio turnover rate was 40% of the average value of its portfolio.
Principal Investment Strategies
The Underlying Index is designed to reflect the performance of a selection of companies that, in aggregate, possess greater exposure to size and value factors relative to the Morningstar Emerging Markets Index (the “Parent Index”), a float-adjusted market-capitalization weighted index of companies incorporated in emerging-market countries. The Underlying Index seeks to achieve increased exposures to size and value factors, or a “factor tilt”, by adjusting the Parent Index’s constituent weights to achieve a slightly greater weight on companies with smaller market capitalizations or lower valuations, as determined by Morningstar, Inc. (the “Index Provider”), pursuant to its index methodology. The Underlying Index is designed to include companies with enhanced risk-return characteristics relative to the broader emerging equity market by featuring size and value risk premiums, which Northern Trust Investments, Inc. (“NTI” or “Investment Adviser”) believes have been historically demonstrated over a full market cycle. As of December 31, 2021, the Underlying Index was comprised of 3,400 issues with market capitalizations ranging from $1.7 billion to $392.3 billion. The Underlying Index is governed by published, objective rules for security selection, 
 

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FlexShares® Morningstar Emerging
Markets Factor Tilt Index Fund (cont.)

exclusion, rebalancing and adjustments for corporate actions and is reconstituted on a semi-annual basis and is rebalanced quarterly. The Fund generally reconstitutes and rebalances its portfolio in accordance with the Underlying Index. 
NTI uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. 
NTI uses a representative sampling strategy to manage the Fund. “Representative sampling” is investing in a representative sample of securities that collectively has an investment profile similar to the Underlying Index. The Fund may or may not hold all of the securities that are included in the Underlying Index. The Fund reserves the right to invest in substantially all of the securities in its Underlying Index in approximately the same proportions (i.e., replication) if NTI determines that it is in the best interest of the Fund. 
Under normal circumstances, the Fund will invest at least 80% of its total assets (exclusive of collateral held from securities lending) in the securities of the Underlying Index and in American Depositary Receipts (“ADRs”) and Global Depositary Receipts (“GDRs”) (collectively “Depositary Receipts”) based on the securities in the Underlying Index. The Fund may also invest up to 20% of its assets in cash and cash equivalents, including shares of money market funds advised by NTI or its affiliates, futures contracts, options on futures contracts and forward currency contracts, as well as securities not included in the Underlying Index, but which NTI believes will help the Fund track its Underlying Index. 
The Underlying Index is sponsored by the Index Provider, an organization that is independent of the Fund and NTI. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. 
The Fund may lend securities representing up to one-third of the value of the Fund’s total assets (including the value of the collateral received). 
From time to time the Fund may focus its investments (i.e., invest more than 15% of its total assets) in one or more 
particular countries or geographic regions. As of December 31, 2021, the Fund focused its investments in China, Taiwan and South Korea. 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. 
Principal Risks
As with any investment, you could lose all or part of your investment in the Fund, and the Fund’s performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.
Equity Securities Risk is the risk that the values of the equity securities owned by the Fund may be more volatile and underperform other asset classes and the general securities markets.
Mid and Small Cap Stock Risk is the risk that stocks of mid-sized and smaller companies may be more volatile than stocks of larger, more established companies, and may lack sufficient market liquidity. Mid-sized and small companies may have limited product lines or financial resources, may be dependent upon a particular niche of the market, or may be dependent upon a small or inexperienced management group. Securities of smaller companies may trade less frequently and in lower volume than the securities of larger companies, which could lead to higher transaction costs. Generally the smaller the company size, the greater the risk.
 
Emerging Markets Risk is the risk that emerging markets are generally subject to greater market volatility, political, social and economic instability, uncertain trading markets and more governmental limitations on foreign investments than more developed markets. In addition, companies operating in emerging markets may be subject to lower trading volumes and greater price volatility than compa- 
 

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FlexShares® Morningstar Emerging
Markets Factor Tilt Index Fund (cont.)

nies in more developed markets. Emerging market economies may be based on only a few industries, may be highly vulnerable to changes in local and global trade conditions, and may suffer from extreme and volatile debt burdens or inflation rates. Companies in emerging market countries generally may be subject to less stringent regulatory, disclosure, financial reporting, accounting, auditing and recordkeeping standards than companies in more developed countries. As a result, information, including financial information, about such companies may be less available and reliable, which can impede the Fund’s ability to evaluate such companies. Securities law and the enforcement of systems of taxation in many emerging market countries may change quickly and unpredictably, and the ability to bring and enforce actions (including bankruptcy, confiscatory taxation, expropriation, nationalization of a company’s assets, restrictions on foreign ownership of local companies, restrictions on withdrawing assets from the country, protectionist measures and practices such as share blocking), or to obtain information needed to pursue or enforce such actions, may be limited. Investments in emerging market securities may be subject to additional transaction costs, delays in settlement procedures, unexpected market closures, and lack of timely information. 
Foreign Securities Risk is the risk that investing in foreign (non-U.S.) securities may result in the Fund experiencing more rapid and extreme changes in value than a fund that invests exclusively in securities of U.S. companies, due to less liquid markets and adverse economic, political, diplomatic, financial, and regulatory factors. Foreign governments may impose limitations on foreigners’ ownership of interests in local issuers, restrictions on the ability to repatriate assets, and may also impose taxes. Any of these events could cause the value of the Fund’s investments to decline. Foreign banks, agents and securities depositories that hold the Fund’s foreign assets may be subject to little or no regulatory oversight over, or independent evaluation, of their operations. Additional costs associated with investments in foreign securities may include higher custodial fees than those applicable to domestic custodial arrangements and transaction costs of foreign currency conversions. Unless the Fund has hedged its foreign currency exposure, foreign securities risk also involves the risk of negative foreign currency rate fluctuations, which may cause the value of securities denominated in such foreign 
currency (or other instruments through which the Fund has exposure to foreign currencies) to decline in value. Currency exchange rates may fluctuate significantly over short periods of time. Currency hedging strategies, if used, are not always successful. For instance, forward foreign currency exchange contracts, if used by the Fund, could reduce performance if there are unanticipated changes in currency exchange rates. 
Geographic Risk is the risk that if a fund invests a significant portion of its total assets in certain issuers within the same country or geographic region, an economic, business or political development affecting that country or region may affect the value of the fund’s investments more than if the fund’s investments were not so concentrated in such country or region. 
China Investment Risk is the risk associated with investments in companies located or operating in China, such as nationalization, expropriation, or confiscation of property; alteration or discontinuation of economic reforms; and considerable degrees of economic, political and social instability. Investors in Chinese markets generally experience difficulties in obtaining information necessary for investigations into and/or litigation against Chinese companies, as well as in obtaining and/or enforcing judgements due to a lack of publicly available information; and there are generally limited legal remedies for shareholders. Internal social unrest or confrontations with other neighboring countries, including military conflicts, may disrupt economic development in China and result in a greater risk of currency fluctuations, currency convertibility, interest rate fluctuations and higher rates of inflation. Export growth continues to be a major driver of China’s rapid economic growth. As a result, a reduction in spending on Chinese products and services, the institution of additional tariffs or other trade barriers, including as a result of heightened trade tensions between China and the U.S., or a downturn in any of the economies of China’s key trading partners may have an adverse impact on the Chinese economy. The inability of the Public Company Accounting Oversight Board (“PCAOB”) to inspect audit work papers and practices of PCAOB-registered accounting firms in China with respect to their audit work of U.S. reporting companies may impose significant additional risks associated with investments in China. Certain securities issued by companies located or operating in China, such as China 
 

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FlexShares® Morningstar Emerging
Markets Factor Tilt Index Fund (cont.)

  A-shares, are subject to trading restrictions and suspensions, quota limitations and sudden changes in those limitations, and operational, clearing and settlement risks.
Taiwan Investment Risk is the risk of investing in securities of Taiwanese issuers. Specifically, Taiwan’s geographic proximity and history of political contention with China have resulted in ongoing tensions between the two countries, which may materially affect the Taiwanese economy and its securities market. Investments in securities of Taiwanese companies are subject to Taiwan’s heavy dependence on exports. Reductions in spending on Taiwanese products and services, labor shortages, institution of tariffs or other trade barriers, or a downturn in any of the economies of Taiwan’s key trading partners, including the United States, may have an adverse impact on the Taiwanese economy and the values of Taiwanese companies.
South Korea Investment Risk is the risk that South Korean issuers in which the Fund invests may subject the Fund to legal, regulatory, political, currency, security, and economic risks that are specific to South Korea. In addition, economic and political developments of South Korea’s neighbors, including escalated tensions involving North Korea and any outbreak of hostilities involving North Korea, or even the threat of an outbreak of hostilities, may have a severe adverse effect on the South Korean economy. 
Concentration Risk is the risk that, if the Fund is concentrated in a particular industry or group of industries, the Fund is likely to present more risks than a fund that is broadly diversified over several industries or groups of industries. Compared to the broad market, an individual industry may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock or regulatory changes. 
Depositary Receipts Risk Foreign securities may trade in the form of depositary receipts. In addition to investment risks associated with the underlying issuer, depositary receipts may expose the Fund to additional risks associated with non-uniform terms that apply to depositary receipt programs, including credit exposure to the depository bank and to the sponsors and other parties with whom the depository bank establishes the programs, currency, political, economic, market risks and the risks of an illiquid market for depositary receipts. Depositary receipts are generally 
subject to the same risks as the foreign securities that they evidence or into which they may be converted. Depositary receipts may not track the price of the underlying foreign securities on which they are based, may have limited voting rights, and may have a distribution subject to a fee charged by the depository. As a result, equity shares of the underlying issuer may trade at a discount or premium to the market price of the depositary receipts. 
Market Risk is the risk that the value of the Fund’s investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude of such changes in value cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, changes in interest rates, lack of liquidity in the bond or equity markets, or volatility in the equity markets. Market disruptions caused by local or regional events such as war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor sentiment could have a significant impact on the Fund and its investments and could result in the Fund’s shares trading at increased premiums or discounts to the Fund’s NAV. An outbreak of COVID-19, a respiratory disease caused by a novel coronavirus, has negatively affected the worldwide economy, the financial health of individual companies and the market in significant and unforeseen ways. The future impact of COVID-19 is currently unknown. The effects to public health, business and market conditions resulting from the COVID-19 pandemic may have a significant negative impact on the performance of the Fund’s investments. During periods of market disruption or other abnormal market conditions, the Fund’s exposure to the risks described elsewhere in this summary will likely increase. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track its Underlying Index or cause delays in the Underlying Index’s rebalancing or reconstitution schedule. During any such delay, it is possible that the Underlying Index and, in turn, the Fund will deviate from the Underlying Index’s stated methodology and therefore experience returns different than those that 
 

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Markets Factor Tilt Index Fund (cont.)

would have been achieved under a normal rebalancing or reconstitution schedule. Because the Fund is designed to maintain a high level of exposure to its Underlying Index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns. 
Market risk includes the risk that a particular style of investing, such as growth or value, may underperform the market generally. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global economies and financial markets. As a result, whether or not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected. Securities markets may experience great short-term volatility and may fall sharply at times. Different markets may behave differently from each other and a foreign market may move in the opposite direction from the U.S. market. 
Price changes may be temporary or last for extended periods. You could lose money over short periods due to fluctuation in the market prices of the Fund’s shares in response to market movements, and over longer periods during market downturns. 
Index Risk is the risk that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Underlying Index, even if that security generally is underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of an index. Additionally, the Fund rebalances and/or reconstitutes its portfolio in accordance with the Underlying Index, and, therefore, any changes to the Underlying Index’s rebalance and/or reconstitution schedule will result in corresponding changes to the Fund’s rebalance and/or reconstitution schedule. 
Tracking Error Risk is the risk that the Fund’s performance may vary substantially from the performance of the Underlying Index. The Fund’s performance may vary from the performance of the Underlying Index for a number of reasons including that the Fund incurs operating expenses that the Underlying Index does not and that the Fund 
accepts custom baskets. Tracking error risk may be higher for funds that track a foreign index, or an index that includes foreign securities, because regulatory and reporting requirements may differ from those in the U.S., and there is a heightened risk associated with limited availability and reliability of data used to construct the index. 
Sampling Risk is the risk that the Fund’s use of a representative sampling approach may result in increased tracking error because the securities selected for the Fund in the aggregate may vary from the investment profile of the Underlying Index. Additionally, the use of a representative sampling approach may result in the Fund holding a smaller number of securities than the Underlying Index, and, as a result, an adverse development to an issuer of securities that the Fund holds could result in a greater decline in NAV than would be the case if the Fund held all of the securities in the Underlying Index. 
Value Investing Risk is the risk that the Fund’s investment in companies whose securities are believed to be undervalued, relative to their underlying profitability, will not appreciate in value as anticipated. 
Authorized Participant Concentration Risk is the risk that the Fund may be adversely affected because it has a limited number of institutions that act as authorized participants (“Authorized Participants”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. This risk may be heightened because of its investments in non-U.S. securities. 
Calculation Methodology Risk is the risk that the Underlying Index’s calculation methodology or sources of information may not provide an accurate assessment of included issuers or correct valuation of securities, nor is the availability or timeliness of the production of the Index guaranteed. A security included in an Underlying Index may not exhibit the characteristic or provide the specific 
 

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FlexShares® Morningstar Emerging
Markets Factor Tilt Index Fund (cont.)

exposure for which it was selected and consequently a Fund's holdings may not exhibit returns consistent with that characteristic or exposure. Unusual market conditions may cause the provider of the Underlying Index to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Market Trading Risk is the risk that the Fund faces because its shares are listed on a securities exchange, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS MAY LEAD TO THE FUND’S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of its listing exchange, make trading in the shares inadvisable. The market prices of Fund shares will generally fluctuate in accordance with changes in its NAV, changes in the relative supply of, and demand for, Fund shares, and changes in the liquidity, or the perceived liquidity, of the Fund’s holdings. 
Derivatives Risk is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instruments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments. 
Futures Contracts Risk is the risk that there will be imperfect correlation between the change in market value of the Fund’s securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of NTI to correctly predict the direction of securities’ prices, interest rates, currency exchange rates and other 
  economic factors, which may make the Fund’s returns more volatile or increase the risk of loss.
Options Contracts Risk Options contracts give the holder of the option the right to buy (or to sell) a position in a security or in a contract to the writer of the option, at a certain price. They are subject to correlation risk because there may be an imperfect correlation between the options and the securities markets that cause a given transaction to fail to achieve its objectives. The successful use of options depends on the investment adviser’s ability to predict correctly future price fluctuations and the degree of correlation between the options and securities markets. Exchanges can limit the number of positions that can be held or controlled by the Fund or the investment adviser, thus limiting the ability to implement the Fund’s strategies.
Forward Foreign Currency Contracts Risk is the risk that, if forward prices increase, a loss will occur to the extent that the agreed upon purchase price of the currency exceeds the price of the currency that was agreed to be sold. 
Securities Lending Risk is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. 
Valuation Risk is the risk that the sale price the Fund could receive for a portfolio security may differ from the Fund’s valuation of the security, particularly for securities that trade in low volume or volatile markets or that are valued using a fair value methodology. In addition, the value of the securities in the Fund’s portfolio may change on days when shareholders will not be able to purchase or sell the Fund’s shares. 
It is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank. 
Fund Performance
The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund. Past performance (before and after taxes) does not necessarily indicate how
 

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Markets Factor Tilt Index Fund (cont.)

the Fund will perform in the future. Updated information on the Fund’s performance results can be obtained by visiting flexshares.com
Calendar Year Total Returns
For the periods in the bar chart above:
Best Quarter (12/31/2020): 22.97%
Worst Quarter (3/31/2020): -27.43%
Average Annual Total Returns
(for the periods ended December 31, 2021)
  One
Year
Five
Year
Since
Inception
of Fund
Inception
Date
of Fund
Before Taxes 5.39% 8.28% 4.21% 9/25/2012
After Taxes on Distributions 4.61%
7.64%
3.70%
After Taxes on Distributions and Sale of Shares 3.75% 6.51% 3.28%
Morningstar® Emerging Markets Factor Tilt IndexSM* 6.42% 9.12% 4.96%
* Reflects no deduction for fees, expenses or taxes.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement plans. After-tax returns may exceed the return before taxes due to an assumed tax benefit from realizing a capital loss on a sale of Fund shares.
Management
Investment Adviser and Portfolio Managers. NTI, a subsidiary of Northern Trust Corporation, serves as the Invest-
ment Adviser of the Fund. Robert Anstine, Brendan Sullivan and Volter Bagriy, each a Vice President of NTI, have served as Portfolio Managers of the Fund since October 2013, June 2016 and March 2021, respectively.
Purchase and Sale of Fund Shares
The Fund is an exchange-traded fund (commonly referred to as an “ETF”). The Fund’s shares may be issued and redeemed only by certain large institutions, referred to as “Authorized Participants,” that enter into agreements with the Fund’s principal underwriter. Retail investors may acquire and sell Fund shares in the secondary market through a broker-dealer. The price of Fund shares is based on market price, and because ETF shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the Fund (bid) and the lowest price a seller is willing to accept for shares of the Fund (ask) when buying or selling shares in the secondary market (“the bid-ask spread”). Recent information, including information about the Fund’s NAV, market price, premiums and discounts, and bid-ask spreads, is included on the Fund’s website at flexshares.com.
Tax Information
The Fund’s distributions are generally taxable to you as ordinary income, qualified dividends, capital gains, or a combination of the three, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account. Distributions may be taxable upon withdrawal from tax-advantaged accounts.
Payments to Brokers-Dealers and Other Financial Intermediaries
If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), NTI and its related companies may pay the intermediary for activities related to the marketing and promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.
 

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FlexShares® US Quality Large Cap Index Fund

Investment Objective
The Fund seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the Northern Trust Quality Large Cap IndexSM (the “Underlying Index”).
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Under the Fund’s Investment Advisory Agreement, the Fund is responsible for the following other expenses: interest expenses, brokerage commissions and other trading expenses, fees and expenses of the independent trustees and their independent legal counsel, taxes and other extraordinary costs such as litigation and other expenses not incurred in the ordinary course of business. You will also incur usual and customary brokerage commissions and fees to financial intermediaries when buying or selling shares of the Fund in the secondary market, which are not reflected in the example that follows:
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fees 0.32%
Distribution (12b-1) Fees 0.00%
Other Expenses 0.01%
Total Annual Fund Operating Expenses 0.33%
Expense Reimbursement(1) -0.01%
Total Annual Fund Operating Expenses After Expense Reimbursement 0.32%
(1) Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than Acquired Fund Fees and Expenses) to the extent the “Total Annual Fund Operating Expenses” exceed 0.32%. This contractual limitation may not be terminated before March 1, 2023 without the approval of the Fund’s Board of Trustees. The Fund’s Board of Trustees may terminate the contractual agreement at any time if it determines that it is in the best interest of the Fund and its shareholders.
Example
The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5%
return each year and that the Fund’s operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year $33
3 Years $105
5 Years $184
10 Years $417
Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. Portfolio turnover may vary from year to year, as well as within a year. During the most recent fiscal year, the Fund’s portfolio turnover rate was 30% of the average value of its portfolio.
Principal Investment Strategies
The Underlying Index is designed to reflect the performance of a selection of companies that, in aggregate, possess greater exposure to quality, value and momentum factors relative to a universe of publicly-traded U.S. large-capitalization equity securities. This universe (the “Starting Universe”) is comprised of the 600 largest companies in the Northern Trust 1250 Index, a float-adjusted market-capitalization weighted index of U.S. domiciled companies. The Underlying Index is designed to include companies with enhanced risk-return characteristics relative to the broader U.S. large-cap equity market by featuring quality, value and momentum risk premiums, which Northern Trust Investments, Inc. (“NTI” or “Investment Adviser”) believes have been historically demonstrated over a full market cycle.
To derive the Underlying Index, NTI, acting in its capacity as index provider (the “Index Provider”), ranks all constituents of the Starting Universe using a Northern Trust proprietary blended multi-factor score. This score is designed to measure companies based on the quantitative assessment of their respective (a) quality (i.e., a factor that seeks to identify companies that exhibit financial strength 
 

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FlexShares® US Quality Large Cap Index Fund (cont.)

and stability relative to the Starting Universe; (b) value (i.e., a factor reflecting the current worth a company relative to its own historical value, book value or valuation versus peers); and (c) momentum (i.e., a factor that reflects market sentiment and changes in security price over a given time period). The Index Provider then uses an optimization process to select and weight eligible securities in order to maximize the overall blended multi-factor score relative to the Starting Universe. The optimization also includes sector, industry group, single-security weight, historical beta (i.e. market sensitivity, relative to the Parent Index) and turnover constraints so that these index characteristics vary within acceptable bands relative to the Starting Universe. The Underlying Index is governed by published, objective rules for security selection, exclusion, rebalancing and adjustments for corporate actions. The Underlying Index is reconstituted on a quarterly basis. The Fund generally reconstitutes its portfolio in accordance with the Underlying Index. As of December 31, 2021, the Underlying Index was comprised of 164 securities with a market capitalization ranging from $11.8 billion to $2.9 trillion. 
NTI uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. 
NTI uses a representative sampling strategy to manage the Fund. “Representative sampling” is investing in a representative sample of securities that collectively has an investment profile similar to the Underlying Index. The Fund may or may not hold all of the securities that are included in the Underlying Index. The Fund reserves the right to invest in substantially all of the securities in its Underlying Index in approximately the same proportions (i.e., replication) if NTI determines that it is in the best interest of the Fund. 
The Fund generally will invest under normal circumstances at least 80% of its total assets (exclusive of collateral held from securities lending) in the securities of its Underlying Index. The Fund may also invest up to 20% of its assets in cash and cash equivalents, including shares of money market funds advised by NTI or its affiliates, futures contracts and options on futures, as well as securities not included in the Underlying Index, but which NTI believes will help the Fund track its Underlying Index. 
The Underlying Index is created and sponsored by NTI, as the Index Provider. NTI also serves as the investment adviser to the Fund. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. 
The Fund may lend securities representing up to one-third of the value of the Fund’s total assets (including the value of the collateral received). 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. 
Principal Risks
As with any investment, you could lose all or part of your investment in the Fund, and the Fund’s performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.
Equity Securities Risk is the risk that the values of the equity securities owned by the Fund may be more volatile and underperform other asset classes and the general securities markets.
Concentration Risk is the risk that, if the Fund is concentrated in a particular industry or group of industries, the Fund is likely to present more risks than a fund that is broadly diversified over several industries or groups of industries. Compared to the broad market, an individual industry may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock or regulatory changes.
 
Market Risk is the risk that the value of the Fund’s investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude of such changes in value cannot be predicted. Certain secu- 
 

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FlexShares® US Quality Large Cap Index Fund (cont.)

rities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, changes in interest rates, lack of liquidity in the bond or equity markets, or volatility in the equity markets. Market disruptions caused by local or regional events such as war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor sentiment could have a significant impact on the Fund and its investments and could result in the Fund’s shares trading at increased premiums or discounts to the Fund’s NAV. An outbreak of COVID-19, a respiratory disease caused by a novel coronavirus, has negatively affected the worldwide economy, the financial health of individual companies and the market in significant and unforeseen ways. The future impact of COVID-19 is currently unknown. The effects to public health, business and market conditions resulting from the COVID-19 pandemic may have a significant negative impact on the performance of the Fund’s investments. During periods of market disruption or other abnormal market conditions, the Fund’s exposure to the risks described elsewhere in this summary will likely increase. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track its Underlying Index or cause delays in the Underlying Index’s rebalancing or reconstitution schedule. During any such delay, it is possible that the Underlying Index and, in turn, the Fund will deviate from the Underlying Index’s stated methodology and therefore experience returns different than those that would have been achieved under a normal rebalancing or reconstitution schedule. Because the Fund is designed to maintain a high level of exposure to its Underlying Index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns. 
Market risk includes the risk that a particular style of investing, such as growth or value, may underperform the market generally. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global economies and financial markets. As a result, whether or 
not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected. Securities markets may experience great short-term volatility and may fall sharply at times. Different markets may behave differently from each other and a foreign market may move in the opposite direction from the U.S. market. 
Price changes may be temporary or last for extended periods. You could lose money over short periods due to fluctuation in the market prices of the Fund’s shares in response to market movements, and over longer periods during market downturns. 
Index Risk is the risk that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Underlying Index, even if that security generally is underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of an index. Additionally, the Fund rebalances and/or reconstitutes its portfolio in accordance with the Underlying Index, and, therefore, any changes to the Underlying Index’s rebalance and/or reconstitution schedule will result in corresponding changes to the Fund’s rebalance and/or reconstitution schedule. 
Tracking Error Risk is the risk that the Fund’s performance may vary substantially from the performance of the Underlying Index. The Fund’s performance may vary from the performance of the Underlying Index for a number of reasons including that the Fund incurs operating expenses that the Underlying Index does not and that the Fund accepts custom baskets. 
Sampling Risk is the risk that the Fund’s use of a representative sampling approach may result in increased tracking error because the securities selected for the Fund in the aggregate may vary from the investment profile of the Underlying Index. Additionally, the use of a representative sampling approach may result in the Fund holding a smaller number of securities than the Underlying Index, and, as a result, an adverse development to an issuer of securities that the Fund holds could result in a greater decline in NAV than would be the case if the Fund held all of the securities in the Underlying Index. 
Momentum Risk is the risk that securities that have had positive momentum compared to other securities may be more volatile than a broad cross-section of securities or 
 

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FlexShares® US Quality Large Cap Index Fund (cont.)

that returns on securities that have previously exhibited positive momentum are less than returns on other securities or the overall stock market. Momentum can turn quickly and cause significant variation from other types of investments. 
Value Investing Risk is the risk that the Fund’s investment in companies whose securities are believed to be undervalued, relative to their underlying profitability, will not appreciate in value as anticipated. 
Quality Factor Risk is the risk that the past performance of companies that have exhibited quality characteristics does not continue or the returns on securities issued by such companies may be less than returns from other styles of investing or the overall stock market. There may be periods when quality investing is out of favor and during which time the Fund's performance may suffer. 
Authorized Participant Concentration Risk is the risk that the Fund may be adversely affected because it has a limited number of institutions that act as authorized participants (“Authorized Participants”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. 
Calculation Methodology Risk is the risk that the Underlying Index’s calculation methodology or sources of information may not provide an accurate assessment of included issuers or correct valuation of securities, nor is the availability or timeliness of the production of the Index guaranteed. A security included in an Underlying Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently a Fund's holdings may not exhibit returns consistent with that characteristic or exposure. Unusual market conditions may cause the provider of the Underlying Index to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Market Trading Risk is the risk that the Fund faces because its shares are listed on a securities exchange, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS MAY LEAD TO THE FUND’S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of its listing exchange, make trading in the shares inadvisable. The market prices of Fund shares will generally fluctuate in accordance with changes in its NAV, changes in the relative supply of, and demand for, Fund shares, and changes in the liquidity, or the perceived liquidity, of the Fund’s holdings. 
Derivatives Risk is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instruments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments. 
Futures Contracts Risk is the risk that there will be imperfect correlation between the change in market value of the Fund’s securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of NTI to correctly predict the direction of securities’ prices, interest rates, currency exchange rates and other economic factors, which may make the Fund’s returns more volatile or increase the risk of loss.
Options Contracts Risk Options contracts give the holder of the option the right to buy (or to sell) a position in a security or in a contract to the writer of the option, at a certain price. They are subject to correlation risk because there may be an imperfect correlation 
 

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  between the options and the securities markets that cause a given transaction to fail to achieve its objectives. The successful use of options depends on the investment adviser’s ability to predict correctly future price fluctuations and the degree of correlation between the options and securities markets. Exchanges can limit the number of positions that can be held or controlled by the Fund or the investment adviser, thus limiting the ability to implement the Fund’s strategies. 
Securities Lending Risk is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. 
It is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank. 
Fund Performance
The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated information on the Fund’s performance results can be obtained by visiting flexshares.com.
Calendar Year Total Returns
For the periods in the bar chart above:
Best Quarter (6/30/2020): 20.80%
Worst Quarter (3/31/2020): -21.73%
Average Annual Total Returns
(for the periods ended December 31, 2021)
  One
Year
Five
Year
Since
Inception
of Fund
Inception
Date
of Fund
Before Taxes 28.51% 15.21% 14.34% 9/23/2015
After Taxes on Distributions 28.18%
14.78%
13.89%
After Taxes on Distributions and Sale of Shares 17.06% 12.15% 11.56%
S&P 500 Index* 28.71% 18.47% 17.65%
Northern Trust Quality Large Cap IndexSM* 28.93% 15.52% 14.67%
* Reflects no deduction for fees, expenses or taxes.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement plans. After-tax returns may exceed the return before taxes due to an assumed tax benefit from realizing a capital loss on a sale of Fund shares.
Management
Investment Adviser and Portfolio Managers. NTI, a subsidiary of Northern Trust Corporation, serves as the Investment Adviser of the Fund. Robert Anstine, Brendan Sullivan and Alan Aung, each a Vice President of NTI, have served as Portfolio Managers of the Fund since inception of the Fund in September 2015, June 2016 and March 2021, respectively.
Purchase and Sale of Fund Shares
The Fund is an exchange-traded fund (commonly referred to as an “ETF”). The Fund’s shares may be issued and redeemed only by certain large institutions, referred to as “Authorized Participants,” that enter into agreements with the Fund’s principal underwriter. Retail investors may acquire and sell Fund shares in the secondary market through a broker-dealer. The price of Fund shares is based on market price, and because ETF shares trade at market
 

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FlexShares® US Quality Large Cap Index Fund (cont.)

prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the Fund (bid) and the lowest price a seller is willing to accept for shares of the Fund (ask) when buying or selling shares in the secondary market (“the bid-ask spread”). Recent information, including information about the Fund’s NAV, market price, premiums and discounts, and bid-ask spreads, is included on the Fund’s website at flexshares.com.
Tax Information
The Fund’s distributions are generally taxable to you as ordinary income, qualified dividends, capital gains, or a combination of the three, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account. Distributions may be taxable upon withdrawal from tax-advantaged accounts.
Payments to Brokers-Dealers and Other Financial Intermediaries
If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), NTI and its related companies may pay the intermediary for activities related to the marketing and promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

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FlexShares® STOXX® US ESG Select Index Fund

Investment Objective
The Fund seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the STOXX® USA ESG Select KPIs IndexSM (the “Underlying Index”).
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Under the Fund’s Investment Advisory Agreement, the Fund is responsible for the following other expenses: interest expenses, brokerage commissions and other trading expenses, fees and expenses of the independent trustees and their independent legal counsel, taxes and other extraordinary costs such as litigation and other expenses not incurred in the ordinary course of business. You will also incur usual and customary brokerage commissions and fees to financial intermediaries when buying or selling shares of the Fund in the secondary market, which are not reflected in the example that follows:
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fees 0.32%
Distribution (12b-1) Fees 0.00%
Other Expenses 0.01%
Total Annual Fund Operating Expenses 0.33%
Expense Reimbursement(1) -0.01%
Total Annual Fund Operating Expenses After Expense Reimbursement 0.32%
(1) Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than Acquired Fund Fees and Expenses) to the extent the “Total Annual Fund Operating Expenses” exceed 0.32%. This contractual limitation may not be terminated before March 1, 2023 without the approval of the Fund’s Board of Trustees. The Fund’s Board of Trustees may terminate the contractual agreement at any time if it determines that it is in the best interest of the Fund and its shareholders.
Example
The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5%
return each year and that the Fund’s operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year $33
3 Years $105
5 Years $184
10 Years $417
Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. Portfolio turnover may vary from year to year, as well as within a year. During the most recent fiscal year, the Fund’s portfolio turnover rate was 40% of the average value of its portfolio.
Principal Investment Strategies
The Underlying Index is designed to reflect the performance of a selection of companies that, in aggregate, score better with respect to a set of environmental, social and governance (“ESG”) key performance indicators (“KPIs”) relative to the U.S. companies in the STOXX® Global 1800 Index (the “Parent Index”), a float-adjusted market-capitalization weighted index of companies incorporated in the U.S. and in developed international markets. The Underlying Index seeks to display enhanced ESG and risk-return characteristics relative to the broad U.S. large-cap equity market by featuring ESG-related KPIs as determined by STOXX Ltd. (the “Index Provider”).
To derive the Underlying Index, the Index Provider eliminates all non-U.S. companies from the Parent Index. From the Parent Index, the Index Provider also eliminates companies that (i) are non-complaint based on Sustainalytics Global Standards Screening assessment, (ii) are involved in controversial weapons or (iii) are coal miners. For each remaining company, the KPIs are determined and standardized by industry, and an aggregate ESG score is calculated. The companies with an ESG score lower than the median ESG score within each industry are then dropped 
 

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FlexShares® STOXX® US ESG Select Index Fund (cont.)

from the Underlying Index. The weights of the remaining constituents are then adjusted so that higher scoring ESG companies are assigned greater weights compared to the Parent Index. The maximum weight that can be assigned to a single company is limited to 5% at the time of each index rebalancing or reconstitution. As of December 31, 2021, the Underlying Index consisted of 273 U.S. companies with market capitalizations ranging from $14.8 billion to $2.5 trillion. The Underlying Index is governed by published, objective rules for security selection, exclusion, rebalancing and adjustments for corporate actions and is reviewed on a quarterly basis. The Fund generally reconstitutes or rebalances its portfolio in accordance with the Underlying Index. 
NTI uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. 
NTI uses a representative sampling strategy to manage the Fund. “Representative sampling” is investing in a representative sample of securities that collectively has an investment profile similar to the Underlying Index. The Fund may or may not hold all of the securities that are included in the Underlying Index. The Fund reserves the right to invest in substantially all of the securities in its Underlying Index in approximately the same proportions (i.e., replication) if NTI determines that it is in the best interest of the Fund. 
Under normal circumstances, the Fund will invest at least 80% of its total assets (exclusive of collateral held from securities lending) in the securities of the Underlying Index. The Fund may also invest up to 20% of its assets in cash and cash equivalents, including shares of money market funds advised by NTI or its affiliates, futures contracts and options on futures contracts, as well as securities not included in the Underlying Index, but which NTI believes will help the Fund track its Underlying Index. 
The Underlying Index is sponsored by the Index Provider, an organization that is independent of the Fund and NTI. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. 
The Fund may lend securities representing up to one-third of the value of the Fund’s total assets (including the value of the collateral received). 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. 
Principal Risks
As with any investment, you could lose all or part of your investment in the Fund, and the Fund’s performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.
ESG Investment Risk is the risk that because the Index Provider includes and excludes issuers and assigns weights to issuers in the Underlying Index by applying nonfinancial factors, the Fund may underperform the broader equity market or other funds that do or do not use ESG investment criteria. The ESG methodology of the Underlying Index will affect the Fund’s exposure to certain companies and sectors and may adversely affect the Fund’s performance depending on whether such companies and sectors are in or out of favor. Although the Underlying Index is designed to measure a portfolio of companies with certain ESG characteristics, there is no assurance that the Underlying Index or Fund will be comprised of such securities or that companies that have historically exhibited such characteristics will continue to exhibit such characteristics. There is also the risk that the Fund may have indirect exposure to companies that have been excluded from the Underlying Index through its use of certain derivative instruments.
Currently, there is a lack of common industry standards relating to the development and application of ESG criteria, which may make it difficult to compare the Fund’s principal investment strategies with the investment strate- 
 

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FlexShares® STOXX® US ESG Select Index Fund (cont.)

gies of other funds that integrate certain ESG criteria. The subjective value that investors may assign to certain types of ESG characteristics may differ substantially from that of the assessment by the Index Provider or a data provider. Investors can differ in their views of what constitutes positive or negative ESG characteristics. As a result, the Fund may invest in companies that do not reflect the beliefs and values of any particular investor. A company included in the Underlying Index may not exhibit positive or favorable ESG characteristics. The companies selected by the Index Provider as demonstrating certain ESG characteristics may not be the same companies selected by other index providers or investment managers as exhibiting those characteristics. 
The Index Provider relies on various sources of information regarding an issuer, including information that may be based on assumptions and estimates. ESG information from third-party data providers may be incomplete, inaccurate or unavailable. Neither the Fund nor NTI can offer assurances that the Underlying Index’s methodology or sources of information will provide an accurate assessment of the issuers of the securities included in the Fund’s Underlying Index. The Index Provider uses third-party data that it believes to be reliable, but it does not guarantee the accuracy of such third-party data. Data can vary across providers or within industries. ESG standards differ by region and industry, and a company’s ESG practices or the Index Provider’s or data providers’ assessment of a company’s ESG practices may change over time. Regulatory changes or interpretations regarding the definitions and/or use of ESG criteria could have a material adverse effect on the Fund’s ability to invest in accordance with its investment policies and/or achieve its investment objective. 
Equity Securities Risk is the risk that the values of the equity securities owned by the Fund may be more volatile and underperform other asset classes and the general securities markets. 
Mid Cap Stock Risk is the risk that stocks of mid-sized companies may be subject to more abrupt or erratic market movements than stocks of larger, more established companies, and may lack sufficient market liquidity. Mid-sized companies may have limited product lines or financial resources, and may be dependent upon a particular niche of the market, or may be dependent upon a small or inex- 
perienced management group. Securities of smaller companies may trade less frequently and in lower volume than the securities of larger companies, which could lead to higher transaction costs. Generally the smaller the company size, the greater the risk. 
Concentration Risk is the risk that, if the Fund is concentrated in a particular industry or group of industries, the Fund is likely to present more risks than a fund that is broadly diversified over several industries or groups of industries. Compared to the broad market, an individual industry may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock or regulatory changes. 
Market Risk is the risk that the value of the Fund’s investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude of such changes in value cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, changes in interest rates, lack of liquidity in the bond or equity markets, or volatility in the equity markets. Market disruptions caused by local or regional events such as war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor sentiment could have a significant impact on the Fund and its investments and could result in the Fund’s shares trading at increased premiums or discounts to the Fund’s NAV. An outbreak of COVID-19, a respiratory disease caused by a novel coronavirus, has negatively affected the worldwide economy, the financial health of individual companies and the market in significant and unforeseen ways. The future impact of COVID-19 is currently unknown. The effects to public health, business and market conditions resulting from the COVID-19 pandemic may have a significant negative impact on the performance of the Fund’s investments. During periods of market disruption or other abnormal market conditions, the Fund’s exposure to the risks described elsewhere in this summary will likely increase. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track its Underlying Index or 
 

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FlexShares® STOXX® US ESG Select Index Fund (cont.)

cause delays in the Underlying Index’s rebalancing or reconstitution schedule. During any such delay, it is possible that the Underlying Index and, in turn, the Fund will deviate from the Underlying Index’s stated methodology and therefore experience returns different than those that would have been achieved under a normal rebalancing or reconstitution schedule. Because the Fund is designed to maintain a high level of exposure to its Underlying Index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns. 
Market risk includes the risk that a particular style of investing, such as growth or value, may underperform the market generally. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global economies and financial markets. As a result, whether or not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected. Securities markets may experience great short-term volatility and may fall sharply at times. Different markets may behave differently from each other and a foreign market may move in the opposite direction from the U.S. market. 
Price changes may be temporary or last for extended periods. You could lose money over short periods due to fluctuation in the market prices of the Fund’s shares in response to market movements, and over longer periods during market downturns. 
Index Risk is the risk that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Underlying Index, even if that security generally is underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of an index. Additionally, the Fund rebalances and/or reconstitutes its portfolio in accordance with the Underlying Index, and, therefore, any changes to the Underlying Index’s rebalance and/or reconstitution schedule will result in corresponding changes to the Fund’s rebalance and/or reconstitution schedule. 
Tracking Error Risk is the risk that the Fund’s performance may vary substantially from the performance of the Underlying Index. The Fund’s performance may vary from 
the performance of the Underlying Index for a number of reasons including that the Fund incurs operating expenses that the Underlying Index does not and that the Fund accepts custom baskets. 
Sampling Risk is the risk that the Fund’s use of a representative sampling approach may result in increased tracking error because the securities selected for the Fund in the aggregate may vary from the investment profile of the Underlying Index. Additionally, the use of a representative sampling approach may result in the Fund holding a smaller number of securities than the Underlying Index, and, as a result, an adverse development to an issuer of securities that the Fund holds could result in a greater decline in NAV than would be the case if the Fund held all of the securities in the Underlying Index. 
Authorized Participant Concentration Risk is the risk that the Fund may be adversely affected because it has a limited number of institutions that act as authorized participants (“Authorized Participants”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. 
Calculation Methodology Risk is the risk that the Underlying Index’s calculation methodology or sources of information may not provide an accurate assessment of included issuers or correct valuation of securities, nor is the availability or timeliness of the production of the Index guaranteed. A security included in an Underlying Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently a Fund's holdings may not exhibit returns consistent with that characteristic or exposure. Unusual market conditions may cause the provider of the Underlying Index to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Market Trading Risk is the risk that the Fund faces because its shares are listed on a securities exchange, including the potential lack of an active market for Fund shares, losses 
 

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FlexShares® STOXX® US ESG Select Index Fund (cont.)

from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS MAY LEAD TO THE FUND’S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of its listing exchange, make trading in the shares inadvisable. The market prices of Fund shares will generally fluctuate in accordance with changes in its NAV, changes in the relative supply of, and demand for, Fund shares, and changes in the liquidity, or the perceived liquidity, of the Fund’s holdings. 
Derivatives Risk is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instruments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments. 
Futures Contracts Risk is the risk that there will be imperfect correlation between the change in market value of the Fund’s securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of NTI to correctly predict the direction of securities’ prices, interest rates, currency exchange rates and other economic factors, which may make the Fund’s returns more volatile or increase the risk of loss.
Options Contracts Risk Options contracts give the holder of the option the right to buy (or to sell) a position in a security or in a contract to the writer of the option, at a certain price. They are subject to correlation risk because there may be an imperfect correlation between the options and the securities markets that cause a given transaction to fail to achieve its objectives. The successful use of options depends on the invest- 
  ment adviser’s ability to predict correctly future price fluctuations and the degree of correlation between the options and securities markets. Exchanges can limit the number of positions that can be held or controlled by the Fund or the investment adviser, thus limiting the ability to implement the Fund’s strategies. 
Securities Lending Risk is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. 
It is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank. 
Fund Performance
The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund by showing how the Fund’s total returns have varied from year to year and by showing how the Fund’s average annual total returns compared with a broad measure of market performance and an additional index with characteristics relevant to the Fund. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated information on the Fund’s performance results can be obtained by visiting flexshares.com.
Calendar Year Total Returns
For the periods in the bar chart above:
Best Quarter (6/30/2020): 21.11%
Worst Quarter (3/31/2020): -19.00%
 

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FlexShares® STOXX® US ESG Select Index Fund (cont.)

Average Annual Total Returns
(for the periods ended December 31, 2021)
  One
Year
Five
Year
Since
Inception
of Fund
Inception
Date
of Fund
Before Taxes 28.53% 18.96% 18.51% 7/13/2016
After Taxes on Distributions 28.18%
18.53%
18.06%
After Taxes on Distributions and Sale of Shares 17.09% 15.33% 15.02%
STOXX® USA ESG Select KPIs IndexSM*/** 28.45% 18.37% 17.94%
Russell 1000® Index** 26.46% 18.42% 17.82%
* Formerly known as STOXX® USA ESG Impact IndexSM.
** Reflects no deduction for fees, expenses or taxes.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement plans. After-tax returns may exceed the return before taxes due to an assumed tax benefit from realizing a capital loss on a sale of Fund shares.
Management
Investment Adviser and Portfolio Managers. NTI, a subsidiary of Northern Trust Corporation, serves as the Investment Adviser of the Fund. Robert Anstine and Brendan Sullivan, each a Vice President of NTI, have served as Portfolio Managers of the Fund since its inception in July 2016. Steven Santiccoli, a Vice President of NTI, has served as a Portfolio Manager of the Fund since March 2021.
Purchase and Sale of Fund Shares
The Fund is an exchange-traded fund (commonly referred to as an “ETF”). The Fund’s shares may be issued and redeemed only by certain large institutions, referred to as “Authorized Participants,” that enter into agreements with the Fund’s principal underwriter. Retail investors may acquire and sell Fund shares in the secondary market
through a broker-dealer. The price of Fund shares is based on market price, and because ETF shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the Fund (bid) and the lowest price a seller is willing to accept for shares of the Fund (ask) when buying or selling shares in the secondary market (“the bid-ask spread”). Recent information, including information about the Fund’s NAV, market price, premiums and discounts, and bid-ask spreads, is included on the Fund’s website at flexshares.com.
Tax Information
The Fund’s distributions are generally taxable to you as ordinary income, qualified dividends, capital gains, or a combination of the three, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account. Distributions may be taxable upon withdrawal from tax-advantaged accounts.
Payments to Brokers-Dealers and Other Financial Intermediaries
If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), NTI and its related companies may pay the intermediary for activities related to the marketing and promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.
 

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FlexShares® STOXX® Global ESG Select Index Fund

Investment Objective
The Fund seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the STOXX® Global ESG Select KPIs IndexSM (the “Underlying Index”).
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Under the Fund’s Investment Advisory Agreement, the Fund is responsible for the following other expenses: interest expenses, brokerage commissions and other trading expenses, fees and expenses of the independent trustees and their independent legal counsel, taxes and other extraordinary costs such as litigation and other expenses not incurred in the ordinary course of business. You will also incur usual and customary brokerage commissions and fees to financial intermediaries when buying or selling shares of the Fund in the secondary market, which are not reflected in the example that follows:
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fees 0.42%
Distribution (12b-1) Fees 0.00%
Other Expenses 0.01%
Total Annual Fund Operating Expenses 0.43%
Expense Reimbursement(1) -0.01%
Total Annual Fund Operating Expenses After Expense Reimbursement 0.42%
(1) Northern Trust Investments, Inc. (“NTI” or the “Investment Adviser”) has contractually agreed to reimburse a portion of the operating expenses of the Fund (other than Acquired Fund Fees and Expenses) to the extent the “Total Annual Fund Operating Expenses” exceed 0.42%. This contractual limitation may not be terminated before March 1, 2023 without the approval of the Fund’s Board of Trustees. The Fund’s Board of Trustees may terminate the contractual agreement at any time if it determines that it is in the best interest of the Fund and its shareholders.
Example
The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5%
return each year and that the Fund’s operating expenses remain the same (taking into account the expense reimbursement arrangement for one year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 Year $43
3 Years $137
5 Years $240
10 Years $541
Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. Portfolio turnover may vary from year to year, as well as within a year. During the most recent fiscal year, the Fund’s portfolio turnover rate was 48% of the average value of its portfolio.
Principal Investment Strategies
The Underlying Index is designed to reflect the performance of a selection of companies that, in aggregate, score better with respect to a set of environmental, social and governance (“ESG”) key performance indicators (“KPIs”) relative to the STOXX® Global 1800 Index (the “Parent Index”), a float-adjusted market-capitalization weighted index of companies incorporated in the U.S. and in developed international markets. The Underlying Index seeks to display enhanced ESG and risk-return characteristics relative to the Parent Index by featuring ESG-related KPIs, as determined by STOXX Ltd. (the “Index Provider”).
To derive the Underlying Index, the Index Provider eliminates companies that (i) are non-compliant based on Sustainalytics Global Standards Screening assessment, (ii) are involved in controversial weapons or (iii) are coal miners. For each remaining company, the KPIs are determined and standardized by industry, and an aggregate ESG score is calculated. The companies with an ESG score lower than the median ESG score within each industry are then dropped from the Underlying Index. The weights of the remaining constituents are then adjusted so that higher scoring ESG companies are assigned greater weights compared to the Parent Index. Component weightings may also 
 

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be adjusted to ensure that the weight representation of each country in the Underlying Index does not vary from that in the STOXX® Global 1800 Index by more than +/-1 percentage point and that the weight of a single company is limited to 5% at the time of each index rebalancing or reconstitution. As of December 31, 2021, the Underlying Index consisted of 883 companies with market capitalizations ranging from $2.9 billion to $2.5 trillion. The Underlying Index is governed by published, objective rules for security selection, exclusion, rebalancing and adjustments for corporate actions and is reviewed on a quarterly basis. The Fund generally reconstitutes or rebalances its portfolio in accordance with the Underlying Index. 
NTI uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. 
NTI uses a representative sampling strategy to manage the Fund. “Representative sampling” is investing in a representative sample of securities that collectively has an investment profile similar to the Underlying Index. The Fund may or may not hold all of the securities that are included in the Underlying Index. The Fund reserves the right to invest in substantially all of the securities in its Underlying Index in approximately the same proportions (i.e., replication) if NTI determines that it is in the best interest of the Fund. 
Under normal circumstances, the Fund will invest at least 80% of its total assets (exclusive of collateral held from securities lending) in the securities of the Underlying Index and in American Depositary Receipts (“ADRs”) and Global Depositary Receipts (“GDRs”) (collectively “Depositary Receipts”) based on the securities in the Underlying Index. The Fund may also invest up to 20% of its assets in cash and cash equivalents, including shares of money market funds advised by NTI or its affiliates, futures contracts, options on futures contracts and forward currency contracts, as well as securities not included in the Underlying Index, but which NTI believes will help the Fund track its Underlying Index. The Fund may enter into forward foreign currency exchange contracts in order to facilitate local settlements or to protect against currency exposure in connection with their distributions to shareholders. The Fund does not expect to engage in currency transactions for 
speculative purposes or for purposes of hedging against declines in the value of its assets that are denominated in a foreign currency. 
The Underlying Index is sponsored by the Index Provider, an organization that is independent of the Fund and NTI. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. 
The Fund may lend securities representing up to one-third of the value of the Fund’s total assets (including the value of the collateral received). 
From time to time the Fund may focus its investments (i.e., invest more than 15% of its total assets) in one or more particular countries or geographic regions. 
Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. 
Principal Risks
As with any investment, you could lose all or part of your investment in the Fund, and the Fund’s performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and ability to meet its investment objective. Each risk noted below is considered a principal risk of investing in the Fund, regardless of the order in which it appears. The significance of each risk factor below may change over time and you should review each risk factor carefully.
ESG Investment Risk is the risk that because the Index Provider includes and excludes issuers and assigns weights to issuers in the Underlying Index by applying nonfinancial factors, the Fund may underperform the broader equity market or other funds that do or do not use ESG investment criteria. The ESG methodology of the Underlying Index will affect the Fund’s exposure to certain companies and sectors and may adversely affect the Fund’s performance depending on whether such companies and sectors are in or out of favor. Although the Underlying Index is designed to measure a portfolio of companies with certain 
 

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ESG characteristics, there is no assurance that the Underlying Index or Fund will be comprised of such securities or that companies that have historically exhibited such characteristics will continue to exhibit such characteristics. There is also the risk that the Fund may have indirect exposure to companies that have been excluded from the Underlying Index through its use of certain derivative instruments. 
Currently, there is a lack of common industry standards relating to the development and application of ESG criteria, which may make it difficult to compare the Fund’s principal investment strategies with the investment strategies of other funds that integrate certain ESG criteria. The subjective value that investors may assign to certain types of ESG characteristics may differ substantially from that of the assessment by the Index Provider or a data provider. Investors can differ in their views of what constitutes positive or negative ESG characteristics. As a result, the Fund may invest in companies that do not reflect the beliefs and values of any particular investor. A company included in the Underlying Index may not exhibit positive or favorable ESG characteristics. The companies selected by the Index Provider as demonstrating certain ESG characteristics may not be the same companies selected by other index providers or investment managers as exhibiting those characteristics. 
The Index Provider relies on various sources of information regarding an issuer, including information that may be based on assumptions and estimates. ESG information from third-party data providers may be incomplete, inaccurate or unavailable. Neither the Fund nor NTI can offer assurances that the Underlying Index’s methodology or sources of information will provide an accurate assessment of the issuers of the securities included in the Fund’s Underlying Index. The Index Provider uses third-party data that it believes to be reliable, but it does not guarantee the accuracy of such third-party data. Data can vary across providers or within industries. ESG standards differ by region and industry, and a company’s ESG practices or the Index Provider’s or data providers’ assessment of a company’s ESG practices may change over time. Regulatory changes or interpretations regarding the definitions and/or use of ESG criteria could have a material adverse effect on the Fund’s ability to invest in accordance with its investment policies and/or achieve its investment objective. 
Equity Securities Risk is the risk that the values of the equity securities owned by the Fund may be more volatile and underperform other asset classes and the general securities markets. 
Mid Cap Stock Risk is the risk that stocks of mid-sized companies may be subject to more abrupt or erratic market movements than stocks of larger, more established companies, and may lack sufficient market liquidity. Mid-sized companies may have limited product lines or financial resources, and may be dependent upon a particular niche of the market, or may be dependent upon a small or inexperienced management group. Securities of smaller companies may trade less frequently and in lower volume than the securities of larger companies, which could lead to higher transaction costs. Generally the smaller the company size, the greater the risk. 
Depositary Receipts Risk Foreign securities may trade in the form of depositary receipts. In addition to investment risks associated with the underlying issuer, depositary receipts may expose the Fund to additional risks associated with non-uniform terms that apply to depositary receipt programs, including credit exposure to the depository bank and to the sponsors and other parties with whom the depository bank establishes the programs, currency, political, economic, market risks and the risks of an illiquid market for depositary receipts. Depositary receipts are generally subject to the same risks as the foreign securities that they evidence or into which they may be converted. Depositary receipts may not track the price of the underlying foreign securities on which they are based, may have limited voting rights, and may have a distribution subject to a fee charged by the depository. As a result, equity shares of the underlying issuer may trade at a discount or premium to the market price of the depositary receipts. 
Foreign Securities Risk is the risk that investing in foreign (non-U.S.) securities may result in the Fund experiencing more rapid and extreme changes in value than a fund that invests exclusively in securities of U.S. companies, due to less liquid markets and adverse economic, political, diplomatic, financial, and regulatory factors. Foreign governments may impose limitations on foreigners’ ownership of interests in local issuers, restrictions on the ability to repatriate assets, and may also impose taxes. Any of these events could cause the value of the Fund’s investments to 
 

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decline. Foreign banks, agents and securities depositories that hold the Fund’s foreign assets may be subject to little or no regulatory oversight over, or independent evaluation, of their operations. Additional costs associated with investments in foreign securities may include higher custodial fees than those applicable to domestic custodial arrangements and transaction costs of foreign currency conversions. Unless the Fund has hedged its foreign currency exposure, foreign securities risk also involves the risk of negative foreign currency rate fluctuations, which may cause the value of securities denominated in such foreign currency (or other instruments through which the Fund has exposure to foreign currencies) to decline in value. Currency exchange rates may fluctuate significantly over short periods of time. Currency hedging strategies, if used, are not always successful. For instance, forward foreign currency exchange contracts, if used by the Fund, could reduce performance if there are unanticipated changes in currency exchange rates. 
Concentration Risk is the risk that, if the Fund is concentrated in a particular industry or group of industries, the Fund is likely to present more risks than a fund that is broadly diversified over several industries or groups of industries. Compared to the broad market, an individual industry may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock or regulatory changes. 
Market Risk is the risk that the value of the Fund’s investments may increase or decrease in response to expected, real or perceived economic, political or financial events in the U.S. or global markets. The frequency and magnitude of such changes in value cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in response to changing market conditions, inflation, changes in interest rates, lack of liquidity in the bond or equity markets, or volatility in the equity markets. Market disruptions caused by local or regional events such as war, acts of terrorism, the spread of infectious illness (including epidemics and pandemics) or other public health issues, recessions or other events or adverse investor sentiment could have a significant impact on the Fund and its investments and could result in the Fund’s shares trading at increased premiums or discounts to the Fund’s NAV. An outbreak of COVID-19, a respiratory disease caused by 
a novel coronavirus, has negatively affected the worldwide economy, the financial health of individual companies and the market in significant and unforeseen ways. The future impact of COVID-19 is currently unknown. The effects to public health, business and market conditions resulting from the COVID-19 pandemic may have a significant negative impact on the performance of the Fund’s investments. During periods of market disruption or other abnormal market conditions, the Fund’s exposure to the risks described elsewhere in this summary will likely increase. Market disruptions, regulatory restrictions or other abnormal market conditions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track its Underlying Index or cause delays in the Underlying Index’s rebalancing or reconstitution schedule. During any such delay, it is possible that the Underlying Index and, in turn, the Fund will deviate from the Underlying Index’s stated methodology and therefore experience returns different than those that would have been achieved under a normal rebalancing or reconstitution schedule. Because the Fund is designed to maintain a high level of exposure to its Underlying Index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns. 
Market risk includes the risk that a particular style of investing, such as growth or value, may underperform the market generally. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global economies and financial markets. As a result, whether or not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected. Securities markets may experience great short-term volatility and may fall sharply at times. Different markets may behave differently from each other and a foreign market may move in the opposite direction from the U.S. market. 
Price changes may be temporary or last for extended periods. You could lose money over short periods due to fluctuation in the market prices of the Fund’s shares in response to market movements, and over longer periods during market downturns. 
 

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Index Risk is the risk that the Fund would not necessarily buy or sell a security unless that security is added or removed, respectively, from the Underlying Index, even if that security generally is underperforming, because unlike many investment companies, the Fund does not utilize an investing strategy that seeks returns in excess of an index. Additionally, the Fund rebalances and/or reconstitutes its portfolio in accordance with the Underlying Index, and, therefore, any changes to the Underlying Index’s rebalance and/or reconstitution schedule will result in corresponding changes to the Fund’s rebalance and/or reconstitution schedule. 
Tracking Error Risk is the risk that the Fund’s performance may vary substantially from the performance of the Underlying Index. The Fund’s performance may vary from the performance of the Underlying Index for a number of reasons including that the Fund incurs operating expenses that the Underlying Index does not and that the Fund accepts custom baskets. Tracking error risk may be higher for funds that track a foreign index, or an index that includes foreign securities, because regulatory and reporting requirements may differ from those in the U.S., and there is a heightened risk associated with limited availability and reliability of data used to construct the index. 
Sampling Risk is the risk that the Fund’s use of a representative sampling approach may result in increased tracking error because the securities selected for the Fund in the aggregate may vary from the investment profile of the Underlying Index. Additionally, the use of a representative sampling approach may result in the Fund holding a smaller number of securities than the Underlying Index, and, as a result, an adverse development to an issuer of securities that the Fund holds could result in a greater decline in NAV than would be the case if the Fund held all of the securities in the Underlying Index. 
Authorized Participant Concentration Risk is the risk that the Fund may be adversely affected because it has a limited number of institutions that act as authorized participants (“Authorized Participants”). Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. To the extent that these institutions exit the business or are unable or unwilling to proceed with 
creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able or willing to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. This risk may be heightened because of its investments in non-U.S. securities. 
Calculation Methodology Risk is the risk that the Underlying Index’s calculation methodology or sources of information may not provide an accurate assessment of included issuers or correct valuation of securities, nor is the availability or timeliness of the production of the Index guaranteed. A security included in an Underlying Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently a Fund's holdings may not exhibit returns consistent with that characteristic or exposure. Unusual market conditions may cause the provider of the Underlying Index to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition. 
Market Trading Risk is the risk that the Fund faces because its shares are listed on a securities exchange, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS MAY LEAD TO THE FUND’S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV. 
Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of its listing exchange, make trading in the shares inadvisable. The market prices of Fund shares will generally fluctuate in accordance with changes in its NAV, changes in the relative supply of, and demand for, Fund shares, and changes in the liquidity, or the perceived liquidity, of the Fund’s holdings. 
Geographic Risk is the risk that if a fund invests a significant portion of its total assets in certain issuers within the same country or geographic region, an economic, business or political development affecting that country or region may affect the value of the fund’s investments more than if the fund’s investments were not so concentrated in such country or region. 
Derivatives Risk is the risk that derivatives may pose risks in addition to and greater than those associated with investing directly in securities, currencies and other instru- 
 

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ments, may be illiquid or less liquid, more volatile, more difficult to value and leveraged so that small changes in the value of the underlying instrument may produce disproportionate losses to the Fund. Derivatives are also subject to counterparty risk, which is the risk that the other party to the transaction will not perform its contractual obligations. The use of derivatives is a highly specialized activity that involves investment techniques and risks different from those associated with investments in more traditional securities and instruments. 
Futures Contracts Risk is the risk that there will be imperfect correlation between the change in market value of the Fund’s securities and the price of futures contracts, which may result in the strategy not working as intended; the possible inability of the Fund to sell or close out a futures contract at the desired time or price; losses due to unanticipated market movements, which potentially are unlimited; and the possible inability of NTI to correctly predict the direction of securities’ prices, interest rates, currency exchange rates and other economic factors, which may make the Fund’s returns more volatile or increase the risk of loss.
Options Contracts Risk Options contracts give the holder of the option the right to buy (or to sell) a position in a security or in a contract to the writer of the option, at a certain price. They are subject to correlation risk because there may be an imperfect correlation between the options and the securities markets that cause a given transaction to fail to achieve its objectives. The successful use of options depends on the investment adviser’s ability to predict correctly future price fluctuations and the degree of correlation between the options and securities markets. Exchanges can limit the number of positions that can be held or controlled by the Fund or the investment adviser, thus limiting the ability to implement the Fund’s strategies.
Forward Foreign Currency Contracts Risk is the risk that, if forward prices increase, a loss will occur to the extent that the agreed upon purchase price of the currency exceeds the price of the currency that was agreed to be sold. 
Securities Lending Risk is the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. 
Valuation Risk is the risk that the sale price the Fund could receive for a portfolio security may differ from the Fund’s valuation of the security, particularly for securities that trade in low volume or volatile markets or that are valued using a fair value methodology. In addition, the value of the securities in the Fund’s portfolio may change on days when shareholders will not be able to purchase or sell the Fund’s shares. 
It is possible to lose money on an investment in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation, any other government agency, or The Northern Trust Company, its affiliates, subsidiaries or any other bank. 
Fund Performance
The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund by showing how the Fund’s total returns have varied from year to year and by showing how the Fund’s average annual total returns compared with a broad measure of market performance and an additional index with characteristics relevant to the Fund. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated information on the Fund’s performance results can be obtained by visiting flexshares.com.
Calendar Year Total Returns
For the periods in the bar chart above:
Best Quarter (6/30/2020): 18.93%
Worst Quarter (3/31/2020): -19.31%
 

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Average Annual Total Returns
(for the periods ended December 31, 2021)
  One
Year
Five
Year
Since
Inception
of Fund
Inception
Date
of Fund