Impax Large Cap Fund

(the “Large Cap Fund”)

Summary of Key Information

The Large Cap Fund’s investment objective is to seek long-term growth of capital.

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell Institutional Class or Investor Class shares of the Large Cap Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

This example is intended to help you compare the cost of investing in Institutional Class or Investor Class shares of the Large Cap Fund with the cost of investing in other mutual funds.

The table assumes that an investor invests $10,000 in Institutional Class or Investor Class shares of the Large Cap Fund for the time periods indicated and then redeems all of his or her shares at the end of those periods. The table also assumes that the investment has a 5% return each year, that all dividends and distributions are reinvested and that the Large Cap Fund’s operating expenses remain the same throughout those periods. Although an investor’s actual expenses may be higher or lower than those shown in the table, based on these assumptions his or her expenses would be:

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 shares are held in a taxable account. These transaction costs, which are not reflected in “Annual Fund Operating Expenses” or in the “Example of Expenses,” affect the Large Cap Fund’s performance. During the Large Cap Fund’s most recent fiscal year, the Large Cap Fund’s portfolio turnover rate was 34% of the average value of its portfolio.

The Large Cap Fund follows a sustainable investing approach, investing in companies that the Adviser believes are well positioned to benefit from the transition to a more sustainable global economy, integrating environmental, social and governance (ESG) analysis and ratings into portfolio construction and managing the portfolio within certain risk parameters relative to the Fund’s benchmark universe of S&P 500 Index companies.

The Fund utilizes the Impax Sustainability Lens, a proprietary tool designed to facilitate a systematic review of the economic opportunities and risks associated with the transition to a more sustainable economy. The tool highlights sub-industries with transition tailwinds and headwinds, assisting the investment team in identifying companies that the Adviser believes present attractive opportunities and lower risks.

The Fund’s investment team also utilizes the Impax Systematic ESG Rating, a fundamental, bottom-up rating by the Adviser of a company’s ESG profile. The rating emphasizes management of ESG-related risks, incorporates ESG trends (taking into account progress or regression in a company’s ESG profile) and takes into account any involvement by the company in significant ESG-related controversies.

Under normal market conditions, the Large Cap Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in equity securities (such as common stocks, securities convertible into common or preferred stocks and

warrants) of companies that, when purchased, have capitalizations within the range of the S&P 500 Index as measured by market capitalization. As of December 31, 2022, the S&P 500 Index included companies with market capitalizations ranging from approximately $3.99 billion to $2,058.10 billion.

The Large Cap Fund selects equity securities on a company-by-company basis primarily through the use of fundamental analysis, including ESG analysis. The Fund may take significant positions in one or more sectors, including the information technology sector. The Large Cap Fund is not constrained by any particular investment style, and may therefore invest in “growth” stocks, “value” stocks or a combination of both. Additionally, it may buy stocks in any sector or industry. The portfolio managers currently expect that the Fund typically will hold between 30 and 60 securities positions.

The Large Cap Fund may invest up to 45% of its assets in securities of non-US issuers, including American Depositary Receipts (“ADRs”). The Large Cap Fund may invest no more than 25% of its assets in securities of non-US issuers other than ADRs. The Large Cap Fund’s investments in securities of non-US issuers may include investments in emerging markets.

Under normal market conditions, and as a result of the Adviser’s focus on risks and opportunities accompanying the transition to a more sustainable economy, the Fund is fossil fuel-free - not invested in securities of companies that the Adviser determines derive revenues or profits from exploration, production, refining or processing of thermal coal, oil or gas, or significant (generally more than 5%) revenues or profits from storage, distribution or power generation from the same. However, a company may be included in the portfolio if the Adviser determines that it has established itself as a leader in the transition to a zero-emissions energy economy with reduction objectives that the Adviser believes are aligned with the Paris Agreement’s objective of limiting future warming to 2°C.

regions, the Fund will be subject to the risks associated with such sector(s), country(ies) or region(s) to a greater extent than would be a more broadly diversified fund.

As with all mutual funds, investors may lose money by investing in the Large Cap Fund.

The foregoing descriptions are only summaries. Please see “About the Funds—Principal Risks” on page 119 for more detailed descriptions of the foregoing risks.

The bar chart below presents the calendar year total returns for Institutional Class shares of the Large Cap Fund before taxes. The bar chart is intended to provide some indication of the risk of investing in the Large Cap Fund by showing changes in the Large Cap Fund’s performance from year to year. As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Average Annual Total Returns The performance table below presents the average annual total returns for Institutional Class and Investor Class shares of the Large Cap Fund. The performance table is intended to provide some indication of the risks of investment in the Large Cap Fund by showing how the Large Cap Fund’s average annual total returns compare with the returns of a broad-based securities market index and a performance average of other similar mutual funds, each over a one-year, five-year and since inception period. After-tax performance is presented only for Institutional Class shares of the Fund. After-tax returns for Investor Class shares may vary. After-tax returns are estimated using the highest historical individual federal marginal income tax rates and do not reflect the effect of local, state or foreign taxes. Actual after-tax returns will depend on a shareholder’s own tax situation and may differ from those shown. After-tax returns may not be relevant to shareholders who hold their shares through tax-advantaged arrangements (such as 401(k) plans and individual retirement accounts). As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Impax Small Cap Fund

(the “Small Cap Fund”)

Summary of Key Information

The Small Cap Fund’s investment objective is to seek long-term growth of capital.

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell Institutional Class, Investor Class or Class A shares of the Small Cap Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts for Class A shares if you and your spouse or minor children invest, or agree to invest in the future, at least $50,000 in Class A shares of the Small Cap Fund. More information about these and other discounts is available from your financial intermediary, under “Shareholder Guide—Sales Charges” on page 149 of this Prospectus and under “Distribution and Shareholder Services—Sales Charge Reductions and Waivers” on page 106 in the Statement of Additional Information. Investors investing in the Small Cap Fund through an intermediary should consult Appendix A to this Prospectus, which includes information regarding financial intermediary specific sales charges and related discount policies that apply to purchases through certain specified intermediaries.

This example is intended to help you compare the cost of investing in Institutional Class, Investor Class or Class A shares of the Small Cap Fund with the cost of investing in other mutual funds.

The table assumes that an investor invests $10,000 in Institutional Class, Investor Class or Class A shares of the Small Cap Fund for the time periods indicated and then redeems all of his or her shares at the end of those periods. The table also assumes that the investment has a 5% return each year, that all dividends and distributions are reinvested and that the Small Cap Fund’s operating expenses remain the same throughout those periods. Although an investor’s actual expenses may be higher or lower than those shown in the table, based on these assumptions his or her expenses would be:

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 shares are held in a taxable account. These transaction costs, which are not reflected in “Annual Fund Operating Expenses” or in the “Example of Expenses,” affect the Small Cap Fund’s performance. During the Small Cap Fund’s most recent fiscal year, the Small Cap Fund’s portfolio turnover rate was 38% of the average value of its portfolio.

The Small Cap Fund follows a sustainable investing approach, investing in companies that the Adviser believes are well positioned to benefit from the transition to a more sustainable global economy, integrating environmental, social and governance (ESG) analysis and ratings into portfolio construction and managing the portfolio within certain risk parameters relative to the Fund’s benchmark universe of Russell 2000 Index companies.

The Fund utilizes the Impax Sustainability Lens, a proprietary tool designed to facilitate a systematic review of the economic opportunities and risks associated with the transition to a more sustainable economy. The tool highlights sub-industries with transition tailwinds and headwinds, assisting the investment team in identifying companies that the Adviser believes present attractive opportunities and lower risks.

Under normal market conditions, the Small Cap Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in equity securities (such as common stocks, securities convertible into common or preferred stocks and warrants) of companies that, when purchased, have capitalizations within the range of the Russell 2000 Index as measured by market capitalization. As of December 31, 2022, the Russell 2000 Index included companies with market capitalizations from approximately $6.07 million to $7.93 billion.

The Small Cap Fund selects equity securities on a company-by-company basis primarily through the use of fundamental analysis, including ESG analysis. The Fund may take significant positions in one or more sectors, including the financial services sector. The Small Cap Fund is not constrained by any particular investment style, and may therefore invest in “growth” stocks, “value” stocks or a combination of both. Moreover, it may buy stocks in any sector or industry.

The Small Cap Fund may invest up to 45% of its assets in securities of non-US issuers, including American Depositary Receipts (“ADRs”). The Small Cap Fund may invest no more than 25% of its assets in securities of non-US issuers other than ADRs. The Small Cap Fund’s investments in securities of non-US issuers, if any, may be diversified across multiple countries or geographic regions, or may be focused in a single country or geographic region.

Under normal market conditions, and as a result of the Adviser’s focus on risks and opportunities accompanying the transition to a more sustainable economy, the Fund is fossil fuel-free - not invested in securities of companies that the Adviser determines derive revenues or profits from exploration, production, refining or processing of thermal coal, oil or gas, or significant (generally more than 5%) revenues or profits from storage, distribution or power generation from the same. However, a company may be included in the portfolio if the Adviser determines

that it has established itself as a leader in the transition to a zero-emissions energy economy with reduction objectives that the Adviser believes are aligned with the Paris Agreement’s objective of limiting future warming to 2°C.

As with all mutual funds, investors may lose money by investing in the Small Cap Fund.

The foregoing descriptions are only summaries. Please see “About the Funds—Principal Risks” on page 119 for more detailed descriptions of the foregoing risks.

The bar chart below presents the calendar year total returns for Investor Class shares of the Small Cap Fund before taxes. The bar chart is intended to provide some indication of the risk of investing in the Small Cap Fund by showing changes in the Small Cap Fund’s performance from year to year. As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Average Annual Total Returns The performance table below presents the average annual total returns for Investor Class, Class A and Institutional Class shares of the Small Cap Fund. The performance table is intended to provide some indication of the risks of investment in the Small Cap Fund by showing how the Small Cap Fund’s average annual total returns compare with the returns of a broad-based securities market index and a performance average of other similar mutual funds, each over a one-year, five-year and ten-year period. After-tax performance is presented only for Investor Class shares of the Fund. After-tax returns for Class A and Institutional Class shares may vary. After-tax returns are estimated using the highest historical individual federal marginal income tax rates and do not reflect the effect of local, state or foreign taxes. Actual after-tax returns will depend on a shareholder’s own tax situation and may differ from those shown. After-tax returns may not be relevant to shareholders who hold their shares through tax-advantaged arrangements (such as 401(k) plans and individual retirement accounts). As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Impax US Sustainable Economy Fund

(the “US Sustainable Economy Fund”)

Summary of Key Information

The US Sustainable Economy Fund’s investment objective is to seek long-term growth of capital.

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell Institutional Class, Investor Class or Class A shares of the US Sustainable Economy Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts for Class A shares if you and your spouse or minor children invest, or agree to invest in the future, at least $50,000 in Class A shares of the US Sustainable Economy Fund. More information about these and other discounts is available from your financial intermediary, under “Shareholder Guide—Sales Charges” on page 149 of this Prospectus and under “Distribution and Shareholder Services—Sales Charge Reductions and Waivers” on page 106 in the Statement of Additional Information. Investors investing in the US Sustainable Economy Fund through an intermediary should consult Appendix A to this Prospectus, which includes information regarding financial intermediary specific sales charges and related discount policies that apply to purchases through certain specified intermediaries.

This example is intended to help you compare the cost of investing in Institutional Class, Investor Class or Class A shares of the US Sustainable Economy Fund with the cost of investing in other mutual funds.

The table assumes that an investor invests $10,000 in Institutional Class, Investor Class or Class A shares of the US Sustainable Economy Fund for the time periods indicated and then redeems all of his or her shares at the end of those periods. The table also assumes that the investment has a 5% return each year, that all dividends and distributions are reinvested and that the US Sustainable Economy Fund’s operating expenses remain the same throughout those periods. Although an investor’s actual expenses may be higher or lower than those shown in the table, based on these assumptions his or her expenses would be:

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 shares are held in a taxable account. These transaction costs, which are not reflected in “Annual Fund Operating Expenses” or in the “Example of Expenses,” affect

the US Sustainable Economy Fund’s performance. During the US Sustainable Economy Fund’s most recent fiscal year, the US Sustainable Economy Fund’s portfolio turnover rate was 37% of the average value of its portfolio.

The US Sustainable Economy Fund follows a sustainable investing approach, investing in companies that the Adviser believes are well positioned to benefit from the transition to a more sustainable economy, integrating environmental, social and governance (ESG) analysis into portfolio construction and managing the portfolio within certain risk parameters relative to the Fund’s benchmark universe of Russell 1000 Index companies.

Under normal market conditions, the Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in large-capitalization US equity securities. The Fund also may invest up to 20% of its assets in non-US issuers, including emerging market investments and American Depository Receipts (ADRs).

The Fund employs a systematic investment strategy that integrates proprietary and external tools and metrics in the portfolio construction process. The Fund incorporates the Impax Sustainability Lens, a tool utilized by the Adviser to facilitate a systematic review of the economic opportunities and risks associated with the transition to a more sustainable economy. The tool highlights sub-industries with transition tailwinds and headwinds, enabling the investment team to construct a portfolio weighted towards companies that the Adviser believes present attractive opportunities and lower risks. The Fund may take significant positions in one or more sectors, including the information technology sector.

The Fund also utilizes the Impax Systematic ESG Rating, a fundamental, bottom-up rating by the Adviser of a company’s ESG profile. The rating emphasizes management of ESG-related risks, incorporates ESG trends (taking into account progress or regression in a company’s ESG profile) and takes into account any involvement by the company in significant ESG-related controversies.

Under normal market conditions, and as a result of the Adviser’s focus on risks and opportunities accompanying the transition to a more sustainable economy, the Fund is fossil fuel-free - not invested in securities of companies that the Adviser determines derive revenues or profits from exploration, production, refining or processing of thermal coal, oil or gas, or significant (generally more than 5%) revenues or profits from storage, distribution or power generation from the same. However, a company may be included in the portfolio if the Adviser determines that it has established itself as a leader in the transition to a zero-emissions energy economy with reduction objectives that the Adviser believes are aligned with the Paris Agreement’s objective of limiting future warming to 2⁰C. Under the Fund’s fossil fuel-free investment approach, fossil fuel

holdings are replaced with energy efficiency stocks. This approach is described more fully below under Sustainable Investing in the About the Funds section of this Prospectus.

As with all mutual funds, investors may lose money by investing in the US Sustainable Economy Fund.

The foregoing descriptions are only summaries. Please see “About the Funds—Principal Risks” on page 119 for more detailed descriptions of the foregoing risks.

Prior to March 31, 2021, Impax US Sustainable Economy Fund was known as Pax ESG Beta Quality Fund and the strategy of the Fund differed from its current strategy. Accordingly, performance of the Fund for periods prior to March 31, 2021 may not be representative of the performance the Fund would have achieved had the Fund been following its current strategy.

The bar chart below presents the calendar year total returns for Investor Class shares of the US Sustainable Economy Fund before taxes. The bar chart is intended to provide some indication of the risk of investing in the US Sustainable Economy Fund by showing changes in the US Sustainable Economy Fund’s performance from year to year. As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Average Annual Total Returns The performance table below presents the average annual total returns for Investor Class, Class A and Institutional Class shares of the US Sustainable Economy Fund. The performance table is intended to provide some indication of the risks of investment in the US Sustainable Economy Fund by showing how the US Sustainable Economy Fund’s average annual total returns compare with the returns of a broad-based securities market index and a performance average of other similar mutual funds over a one-year, five-year and ten-year period. After-tax performance is presented only for Investor Class Shares of the Fund. After-tax returns for Class A and Institutional Class shares may vary. After-tax returns are estimated using the highest historical individual federal marginal income tax rates and do not reflect the effect of local, state or

foreign taxes. Actual after-tax returns will depend on a shareholder’s own tax situation and may differ from those shown. After-tax returns may not be relevant to shareholders who hold their shares through tax-advantaged arrangements (such as 401(k) plans and individual retirement accounts). As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Impax Global Sustainable Infrastructure Fund

(the “Global Sustainable Infrastructure Fund”)

Summary of Key Information

The Global Sustainable Infrastructure Fund’s investment objective is capital appreciation and income.

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell Institutional Class or Investor Class shares of the Global Sustainable Infrastructure Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

This example is intended to help you compare the cost of investing in Institutional Class or Investor Class shares of the Global Sustainable Infrastructure Fund with the cost of investing in other mutual funds.

The table assumes that an investor invests $10,000 in Institutional Class or Investor Class shares of the Global Sustainable Infrastructure Fund for the time periods indicated and then redeems all of his or her shares at the end of those periods. The table also assumes that the investment has a 5% return each year, that all dividends and distributions are reinvested and that the Global Sustainable Infrastructure Fund’s operating expenses remain the same throughout those periods. Although an investor’s actual expenses may be higher or lower than those shown in the table, based on these assumptions his or her expenses would be:

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 shares are held in a taxable account. These transaction costs, which are not reflected in “Annual Fund Operating Expenses” or in the “Example of Expenses,” affect the Global Sustainable Infrastructure Fund’s performance. During the Global Sustainable Infrastructure Fund’s most recent fiscal year, the Global Sustainable Infrastructure Fund’s portfolio turnover rate was 54% of the average value of its portfolio.

The Global Sustainable Infrastructure Fund follows a sustainable investing approach, investing in companies that the Adviser believes are well positioned to provide infrastructure essential for the transition to a more sustainable global economy, integrating environmental, social and governance (ESG) analysis and ratings into portfolio construction.

Under normal market conditions, the Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in equity securities of companies that the Adviser determines derive significant revenues (i.e., at least 20% of revenues) from owning, operating, developing or distributing sustainable infrastructure-related goods, services or assets. The Adviser defines “sustainable infrastructure” to mean infrastructure that conserves, enables or increases access to vital resources such as clean energy, water, food and agriculture, including resource and waste

management, as well as other societal resources such as healthcare, education, finance, transportation, and data and communications that advance social well-being.

Under normal market conditions, the Fund will invest in companies located around the world, including at least 40% of its net assets in securities of companies organized or located outside the United States or doing a substantial amount of business outside the United States, including those located in emerging markets. The Fund may take significant positions in one or more sectors, including the industrials and utilities sectors. While the Fund is not limited to equity securities that pay dividends, the Adviser expects that the Fund’s portfolio will normally have a higher dividend yield than the broader equity market.

The Fund employs a systematic investment strategy that integrates proprietary and external tools and metrics in the portfolio construction process. For US companies, the Fund utilizes the Impax Systematic ESG Rating, a fundamental, bottom-up rating by the Adviser of a company’s ESG profile. The rating emphasizes management of ESG-related risks, incorporates ESG trends (taking into account progress or regression in a company’s ESG profile) and takes into account any involvement by the company in significant ESG-related controversies.

For non-US companies or when an Impax Systematic ESG Rating is not available, the Fund utilizes ESG research or ratings provided by Sustainalytics, a Morningstar company whose ESG Risk Ratings measure the degree to which a company’s value is at risk based on ESG factors -- in other words, the magnitude of a company’s unmanaged ESG risk. ESG research or ratings provided by Sustainalytics might reflect assessments that differ from those the Adviser would make. When neither an Impax Systematic ESG Rating nor a Sustainalytics ESG Risk Rating is available, the Fund will utilize proprietary ESG research conducted by the Adviser.

Under normal market conditions, and as a result of the Adviser’s focus on risks and opportunities accompanying the transition to a more sustainable economy, the Fund is fossil fuel-free - not invested in securities of companies that the Adviser determines derive revenues or profits from exploration, production, refining or processing of thermal coal, oil or gas, or significant (generally more than 5%) revenues or profits from storage, distribution or power generation from the same. However, a company may be included in the portfolio if the Adviser determines that it has established itself as a leader in the transition to a zero-emissions energy economy with reduction objectives that the Adviser believes are aligned with the Paris Agreement’s objective of limiting future warming to 2°C.

pandemics such as the COVID-19 outbreak may adversely affect security prices, thereby reducing the value of the Fund’s investments. To the extent the Fund takes significant positions in one or more specific sectors, countries or regions, the Fund will be subject to the risks associated with such sector(s), country(ies) or region(s) to a greater extent than would be a more broadly diversified fund.

insurance costs, and labor relations issues. Companies in the utilities sector could be affected by, among other things, government regulation, overall economic conditions and fuel prices.

As with all mutual funds, investors may lose money by investing in the Global Sustainable Infrastructure Fund.

The foregoing descriptions are only summaries. Please see “About the Funds—Principal Risks” on page 119 for more detailed descriptions of the foregoing risks.

Prior to March 31, 2021, Impax Global Sustainable Infrastructure Fund was known as Pax ESG Beta Dividend Fund and the strategy of the Fund differed from its current strategy. Accordingly, performance of the Fund for periods prior to March 31, 2021 may not be representative of the performance the Fund would have achieved had the Fund been following its current strategy.

Effective November 15, 2022, the FTSE Global Infrastructure Opportunities Index replaced the S&P Global Infrastructure (Net) Index as the primary benchmark for the Global Sustainable Infrastructure Fund because the Adviser believes the FTSE Global Infrastructure Opportunities Index is a more appropriate broad-based securities market index representing the universe of securities in which the Fund may invest.

The bar chart below presents the calendar year total returns for Institutional Class shares of the Global Sustainable Infrastructure Fund before taxes. The bar chart is intended to provide some indication of the risk of investing in the Sustainable Infrastructure Fund by showing changes in the Sustainable Infrastructure Fund’s performance from year to year. As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Average Annual Total Returns The performance table below presents the average annual total returns for Institutional Class and Investor Class shares of the Global Sustainable Infrastructure Fund. The performance table is intended to provide some indication of the risks of investment in the Global Sustainable Infrastructure

Fund by showing how the Global Sustainable Infrastructure Fund’s average annual total returns compare with the returns of a broad-based securities market index and a performance average of other similar mutual funds, each over a one-year, five-year and since inception period. After-tax performance is presented only for Institutional Class shares of the Fund. After-tax returns for Investor Class shares may vary. After-tax returns are estimated using the highest historical individual federal marginal income tax rates and do not reflect the effect of local, state or foreign taxes. Actual after-tax returns will depend on a shareholder’s own tax situation and may differ from those shown. After-tax returns may not be relevant to shareholders who hold their shares through tax-advantaged arrangements (such as 401(k) plans and individual retirement accounts). As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Impax Global Opportunities Fund

(the “Global Opportunities Fund”)

Summary of Key Information

The Global Opportunities Fund’s investment objective is to seek long term growth of capital by investing in companies benefiting from the transition to a more sustainable global economy.

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell Institutional Class or Investor Class shares of the Global Opportunities Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

This example is intended to help you compare the cost of investing in Institutional Class or Investor Class shares of the Global Opportunities Fund with the cost of investing in other mutual funds.

The table assumes that an investor invests $10,000 in Institutional Class or Investor Class shares of the Global Opportunities Fund for the time periods indicated and then redeems all of his or her shares at the end of those periods. The table also assumes that the investment has a 5% return each year, that all dividends and distributions are reinvested and that the Global Opportunities Fund’s operating expenses remain the same throughout those periods. The amounts shown reflect the contractual reimbursement noted in the Annual Fund Operating Expenses table for the first year. Although an investor’s actual expenses may be higher or lower than those shown in the table, based on these assumptions his or her expenses would be:

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 shares are held in a taxable account. These transaction costs, which are not reflected in “Annual Fund Operating Expenses” or in the “Example of Expenses,” affect the Global Opportunities Fund’s performance. During the Global Opportunities Fund’s most recent fiscal year, the Global Opportunities Fund’s portfolio turnover rate was 38% of the average value of its portfolio.

The Global Opportunities Fund follows a sustainable investing approach, investing in companies that the Sub-Adviser believes are well positioned to benefit from the transition to a more sustainable global economy, integrating environmental, social and governance (ESG) analysis and ratings into portfolio construction and managing the portfolio within certain risk parameters relative to the Fund’s benchmark universe of MSCI ACWI Index companies.

The Fund utilizes the Impax Sustainability Lens, a proprietary tool designed to facilitate a systematic review of the economic opportunities and risks associated with the transition to a more sustainable economy. The tool highlights sub-industries with transition tailwinds and headwinds, assisting the investment team in identifying companies that the Sub-Adviser believes present attractive opportunities and lower risks.

Under normal market conditions, the Global Opportunities Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in companies that its Adviser or Sub-Adviser believe will benefit from the transition to a more sustainable global economy – the shift away from a depletive economy to one that preserves ecological and societal balance for the benefit of future generations. The Fund seeks to invest in companies with durable business models that are well positioned to benefit from or avoid the risks associated with this transition. Under normal market conditions, the Global Opportunities Fund will invest primarily in equity securities (such as common stocks, preferred stocks and securities convertible into common or preferred stocks) of companies located around the world, including at least 40% of its net assets in securities of companies organized or located outside the United States or doing a substantial amount of business outside the United States, including those located in emerging markets. The Fund’s investments may be diversified across multiple countries or geographic regions, or may be focused on a select geographic region, although the Global Opportunities Fund will normally have investments in a minimum of three countries other than the United States. The Fund’s investments in securities of non-US issuers may be denominated in currencies other than the US dollar. The Adviser and Sub-Adviser currently expect that the Fund typically will hold between 35 and 45 securities positions.

The Global Opportunities Fund’s Sub-Adviser selects equity securities on a company-by-company basis primarily through the use of fundamental analysis, including ESG analysis. The Global Opportunities Fund is not constrained by any particular investment style, and may therefore invest in “growth” stocks, “value” stocks or a combination of both. Additionally, it may buy stocks in any sector or industry, and it is not limited to investing in securities of a specific market capitalization.

The Global Opportunities Fund seeks to invest in companies with sustainable competitive advantages, track records of consistent returns on investment, and where the Fund’s Sub-Adviser believes a company’s attractive, bottom-up financial characteristics and long-term opportunities are not reflected in its share price.

Under normal market conditions, and as a result of the Adviser’s focus on risks and opportunities accompanying the transition to a more sustainable economy, the Fund is fossil fuel-free - not invested in securities of companies that the Adviser determines derive revenues or profits from exploration, production, refining or processing of thermal coal, oil or gas, or significant (generally more than 5%) revenues or profits from storage, distribution or power generation from the same. However, a company may be included in the portfolio if the Adviser determines that it has established itself as a leader in the transition to a zero-emissions energy economy with reduction objectives that the Adviser believes are aligned with the Paris Agreement’s objective of limiting future warming to 2°C.

As with all mutual funds, investors may lose money by investing in the Global Opportunities Fund.

The foregoing descriptions are only summaries. Please see “About the Funds—Principal Risks” on page 119 for more detailed descriptions of the foregoing risks.

The bar chart below presents the calendar year total returns for Institutional Class shares of the Global Opportunities Fund before taxes. The bar chart is intended to provide some indication of the risk of investing in the Global Opportunities Fund by showing changes in the Global Opportunities Fund’s performance from year to year. As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Average Annual Total Returns The performance table below presents the average annual total returns for Institutional Class and Investor Class shares of the Global Opportunities Fund. The performance table is intended to provide some indication of the risks of investment in the Global Opportunities Fund by showing how the Global Opportunities Fund’s average annual total returns compare with the returns of a broad-based securities market index and a performance average of other similar mutual funds, each over a one-year and since inception period. After-tax performance is presented only for Institutional Class shares of the Fund. After-tax returns for Investor Class shares may vary. After-tax returns are estimated using the highest historical individual federal marginal income tax rates and do not reflect the effect of local, state or foreign taxes. Actual after-tax returns will depend on a shareholder’s own tax situation and may differ from those shown. After-tax returns may not be relevant to shareholders who hold their shares through tax-advantaged arrangements (such as 401(k) plans and individual retirement accounts). As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Impax Global Environmental Markets Fund

(the “Global Environmental Markets Fund”)

Summary of Key Information

The Global Environmental Markets Fund’s investment objective is to seek long term growth of capital by investing in innovative companies around the world whose businesses and technologies focus on environmental markets, including alternative energy and energy management & efficiency; transportation solutions; water infrastructure & technologies; environmental services & resources; resource efficiency & waste management; digital infrastructure; and sustainable food & agriculture.

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell Institutional Class, Investor Class or Class A shares of the Global Environmental Markets Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts for Class A shares if you and your spouse or minor children invest, or agree to invest in the future, at least $50,000 in Class A shares of the Global Environmental Markets Fund. More information about these and other discounts is available from your financial intermediary, under “Shareholder Guide—Sales Charges” on page 149 of this Prospectus and under “Distribution and Shareholder Services—Sales Charge Reductions and Waivers” on page 106 in the Statement of Additional Information. Investors investing in the Global Environmental Markets Fund through an intermediary should consult Appendix A to this Prospectus, which includes information regarding financial intermediary specific sales charges and related discount policies that apply to purchases through certain specified intermediaries.

This example is intended to help you compare the cost of investing in Institutional Class, Investor Class or Class A shares of the Global Environmental Markets Fund with the cost of investing in other mutual funds.

The table assumes that an investor invests $10,000 in Institutional Class, Investor Class or Class A shares of the Global Environmental Markets Fund for the time periods indicated and then redeems all of his or her shares at the end of those periods. The table also assumes that the investment has a 5% return each year, that all dividends and distributions are reinvested and that the Global Environmental Markets Fund’s operating expenses remain the same throughout those periods. Although an investor’s actual expenses may be higher or lower than those shown in the table, based on these assumptions his or her expenses would be:

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 shares are held in a taxable account. These transaction costs, which are not reflected in “Annual Fund Operating Expenses” or in the “Example of Expenses,” affect the Global Environmental Markets Fund’s performance. During the Global Environmental Markets Fund’s most recent fiscal year, the Global Environmental Markets Fund’s portfolio turnover rate was 35% of the average value of its portfolio.

The Global Environmental Markets Fund follows a sustainable investing approach, investing in companies that the Sub-Adviser believes are well positioned to benefit from the transition to a more sustainable global economy, integrating environmental, social and governance (ESG) analysis and ratings into portfolio construction and managing the portfolio within certain risk parameters relative to the Fund’s benchmark universe of MSCI ACWI Index companies.

Under normal market conditions, the Global Environmental Markets Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in companies whose businesses and technologies focus on environmental markets, including alternative energy and energy management & efficiency; transportation solutions; water infrastructure & technologies; environmental services & resources; resource efficiency & waste management; digital infrastructure; and sustainable food & agriculture.

Under normal market conditions, the Global Environmental Markets Fund will invest primarily in equity securities (such as common stocks, preferred stocks and securities convertible into common and preferred stocks) of companies located around the world, including at least 40% of its net assets in securities of non-US issuers, including those located in emerging markets. The Fund’s investments may be diversified across multiple countries or geographic regions, or may be focused on a select geographic region, although the Global Environmental Markets Fund will normally have investments in a minimum of three countries other than the United States. The Fund’s investments in securities of non-US issuers may be denominated in currencies other than the US dollar.

The Global Environmental Markets Fund’s Sub-Adviser selects equity securities on a company-by-company basis primarily through the use of fundamental analysis, including ESG analysis. The Global Environmental Markets Fund is not constrained by any particular investment style, and may therefore invest in “growth” stocks, “value” stocks or a combination of both. Additionally, it may buy stocks in any sector or industry, and it is not limited to investing in securities of a specific market capitalization.

The Global Environmental Markets Fund seeks to invest in companies with positive overall environmental performance and whose products or services help other companies and countries improve their environmental performance, and seeks to avoid investing in companies with significant environmental problems or worsening environmental profiles.

Under normal market conditions, and as a result of the Adviser’s focus on risks and opportunities accompanying the transition to a more sustainable economy, the Fund is fossil fuel-free - not invested in securities of companies that the Adviser determines derive revenues or profits from exploration, production, refining or processing of thermal coal, oil or gas, or significant (generally more than 5%)

revenues or profits from storage, distribution or power generation from the same. However, a company may be included in the portfolio if the Adviser determines that it has established itself as a leader in the transition to a zero-emissions energy economy with reduction objectives that the Adviser believes are aligned with the Paris Agreement’s objective of limiting future warming to 2°C.

As with all mutual funds, investors may lose money by investing in the Global Environmental Markets Fund.

The foregoing descriptions are only summaries. Please see “About the Funds—Principal Risks” on page 119 for more detailed descriptions of the foregoing risks.

The bar chart below presents the calendar year total returns for Investor Class shares of the Global Environmental Markets Fund before taxes. The bar chart is intended to provide some indication of the risk of investing in the Global Environmental Markets Fund by showing changes in the Global Environmental Markets Fund’s performance from year to year. As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Average Annual Total Returns The performance table below presents the average annual total returns for Investor Class, Class A and Institutional Class shares of the Global Environmental Markets Fund. The performance table is intended to provide some indication of the risks of investment in the Global Environmental Markets Fund by showing how the Global Environmental Markets Fund’s average annual total returns compare with the returns of a broad-based securities market index over a one-year, five-year and ten-year period. After-tax performance is presented only for Investor Class shares of the Fund. After-tax returns for Class A and Institutional Class shares may vary. After-tax returns are estimated using the highest historical individual federal marginal income tax rates and do not reflect the effect of local, state or foreign taxes. Actual after-tax returns will depend on a shareholder’s own tax situation and may differ from those shown. After-tax returns may not be relevant to shareholders who hold their shares through tax-advantaged arrangements (such as 401(k) plans and individual retirement accounts). As with all mutual funds, past performance (before and after taxes) is not necessarily an indication of future performance.

Impax International Sustainable Economy Fund

(the “International Sustainable Economy Fund”)

Summary of Key Information

The International Sustainable Economy Fund’s investment objective is to seek long-term growth of capital.

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell Institutional Class or Investor shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

This example is intended to help you compare the cost of investing in Institutional Class or Investor Class shares of the Fund with the cost of investing in other mutual funds.

The table assumes that an investor invests $10,000 in Institutional Class or Investor Class shares of the Fund for the time periods indicated and then redeems all of his or her shares at the end of those periods. The table also assumes that the investment has a 5% return each year, that all dividends and distributions are reinvested and that the Fund’s operating expenses remain the same throughout those periods. Although an investor’s actual expenses may be higher or lower than those shown in the table, based on these assumptions his or her expenses would be:

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 shares are held in a taxable account. These transaction costs, which are not reflected in “Annual Fund Operating Expenses” or in the “Example of Expenses,” affect the Fund’s performance. During the International Sustainable Economy Fund’s most recent fiscal year, the International Sustainable Economy Fund’s portfolio turnover rate was 51% of the average value of the portfolio.

The International Sustainable Economy Fund follows a sustainable investing approach, investing in companies that the Adviser believes are well positioned to benefit from the transition to a more sustainable economy, integrating environmental, social and governance (ESG) ratings into portfolio construction and managing the portfolio within certain risk parameters relative to the Fund’s benchmark universe of MSCI EAFE Index companies.

Under normal market conditions, the Fund invests more than 80% of its net assets (plus any borrowings for investment purposes) in large-capitalization equity securities in non-US developed markets, including American Depository Receipts, Global Depository Receipts and Euro Depository Receipts. The Fund may take significant positions in one or more non-US developed markets, including the Asia and Pacific region and the European Union. The Fund’s investments in securities of non-US issuers may be denominated in currencies other than the U.S. dollar.

The Fund employs a systematic investment strategy that integrates proprietary and external tools and metrics in the portfolio construction process. The Fund incorporates the Impax Sustainability Lens, a tool utilized by the Adviser to facilitate a systematic review of the economic opportunities and risks associated with the transition to a more sustainable economy. The tool highlights sub-

industries with transition tailwinds and headwinds, enabling the investment team to construct a portfolio weighted towards companies that the Adviser believes present attractive opportunities and lower risks.

The Fund also utilizes ESG ratings determined by MSCI ESG Research. MSCI ESG Research evaluates companies’ ESG characteristics and derives corresponding ESG scores and ratings. Companies are ranked by ESG score against sector peers to determine their eligibility for the MSCI ESG indices and for the Fund. The rating system is based on general and industry-specific ESG criteria, assigning ratings on a 9-point scale from AAA (highest) to C (lowest). ESG research or ratings provided by MSCI ESG Research might reflect assessments that differ from those the Adviser would make.

Under normal market conditions, and as a result of the Adviser's focus on risks and opportunities accompanying the transition to a more sustainable economy, the Fund is fossil fuel-free - not invested in securities of companies that the Adviser determines derive revenues or profits from exploration, production, refining or processing of thermal coal, oil or gas, or significant (generally more than 5%) revenues or profits from storage, distribution or power generation from the same. However, a company may be included in the portfolio if the Adviser determines that it has established itself as a leader in the transition to a zero-emissions energy economy with reduction objectives that the Adviser believes are aligned with the Paris Agreement's objective of limiting future warming to 2⁰C. Under the Fund's fossil fuel-free investment approach, fossil fuel holdings are replaced with energy efficiency stocks. This approach is described more fully below under Sustainable Investing in the About the Funds section of this Prospectus.