Summary Prospectus
February 28, 2017

Mirova Global Green Bond Fund

Ticker Symbol: Class A (MGGAX), Class N (MGGNX) and Class Y (MGGYX)

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. You can find the Fund's Prospectus and other information about the Fund online at ngam.natixis.com/us/fund-documents. You can also get this information at no cost by calling 800-225-5478 or by sending an e-mail request to NatixisFunds@ngam.natixis.com. The Fund's Prospectus and Statement of Additional Information, each dated February 28, 2017, as may be revised or supplemented from time to time, are incorporated by reference into this Summary Prospectus.

Investment Goal

The Fund seeks to provide total return, through a combination of capital appreciation and current income, by investing in green bonds.

Fund Fees & Expenses

The following table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in the Natixis Fund Complex. More information about these and other discounts is available from your financial professional and in the section "How Sales Charges Are Calculated" on page 12 of the Prospectus and on page 73 in the section "Reduced Sales Charges" of the Statement of Additional Information ("SAI").

Shareholder Fees

(fees paid directly from your investment)	Class A		Class N	Class Y
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	4.25	%	None	None
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)	None *		None	None
Redemption fees	None		None	None

*A 1.00% contingent deferred sales charge ("CDSC") may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.

Annual Fund Operating Expenses

(expenses that you pay each year as a percentage of the value of your investment)	Class A		Class N		Class Y
Management fees	0.55	%	0.55	%	0.55	%
Distribution and/or service (12b-1) fees	0.25	%	0.00	%	0.00	%
Other expenses 1	0.65	%	0.56	%	0.65	%
Total annual fund operating expenses	1.45	%	1.11	%	1.20	%
Fee waiver and/or expense reimbursement 2	0.50	%	0.46	%	0.50	%
Total annual fund operating expenses after fee waiver and/or expense reimbursement	0.95	%	0.65	%	0.70	%

1Other expenses are estimated for the current fiscal year.

2Natixis Asset Management U.S., LLC ("Natixis AM US" or the "Adviser") has given a binding contractual undertaking to the Fund to limit the amount of the Fund's total annual fund operating expenses to 0.95%, 0.65% and 0.70% of the Fund's average daily net assets for Class A, N and Y shares, respectively, exclusive of brokerage expenses, interest expense, taxes, acquired fund fees and expenses, organizational and extraordinary expenses, such as litigation and indemnification expenses. This undertaking is in effect through April 30, 2018 and may be terminated before then only with the consent of the Fund's Board of Trustees. The Adviser will be permitted to recover, on a class-by-class basis, management fees waived and/or expenses reimbursed to the extent that expenses in later periods fall below the applicable expense limitation for Class A, N and Y shares. The Fund will not be obligated to repay any such waived/reimbursed fees and expenses more than one year after the end of the fiscal year in which the fees or expenses were waived/reimbursed.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual 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 (except where indicated). The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same, except that the example is based on the Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement for the first 14 months and on the Total Annual Fund Operating Expenses for the remaining periods. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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Fund Summary

	1 year		3 years
Class A	$	518	$	808
Class N	$	66	$	299
Class Y	$	72	$	322

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 for you if your 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.

Investments, Risks and Performance

Principal Investment Strategies

Under normal circumstances, the Fund invests at least 80% of its net assets (plus any borrowings made for investment purposes) in "green bonds." "Green bonds" are bonds and notes all of the proceeds of which are used to finance projects which the Adviser believes will have a positive environmental impact. The Fund invests in securities of issuers located in no fewer than three countries, which may include the U.S. Under normal circumstances, the Fund will invest at least 40% of its assets in securities of issuers located outside the U.S. and the Fund may invest up to 20% of its assets in securities of issuers located in emerging markets. The Adviser considers an issuer to be located outside the U.S. if its head office is located outside the U.S. Emerging markets are economies that the Adviser believes are not generally recognized to be fully developed markets, as measured by gross national income, financial market infrastructure, market capitalization and/or other factors. The Fund may invest up to 20% of its assets, at the time of purchase, in securities rated below investment grade (i.e., none of the three major ratings agencies (Moody's Investors Services, Inc., Fitch Investor Services, Inc. or S&P Global Ratings) have rated the securities in one of their top four ratings categories) (commonly known as "junk bonds"), or, if unrated, securities determined by the Adviser to be of comparable quality. The Fund may invest in bonds of any maturity and expects that under normal circumstances the modified duration of its portfolio will range between 0 and 10. This flexibility is intended to allow the portfolio managers to reposition the fund to take advantage of significant interest rate movements. Performance is expected to derive primarily from security selection and duration is not expected to be a major source of excess return relative to the benchmark.

The Fund primarily invests in fixed-income securities issued by companies, banks, supranational entities, development banks, agencies, regions and governments. In deciding which securities to buy and sell, the Adviser selects securities based on their financial valuation profile and an analysis of the global environmental, social and governance ("ESG") impact of the issuer or the projects funded with the securities. Following the evaluation of a security, the portfolio managers value the security based, among other factors, on what they believe is a fair spread for the issue relative to comparable government securities, as well as historical and expected default and recovery rates. The portfolio managers will re-evaluate and possibly sell a security if there is a deterioration of its ESG quality and/or financial rating, among other reasons.

Green bonds are usually issued to finance specific projects intended to generate an environmental benefit while offering potential market return in the same manner as other "conventional" fixed income securities. Beyond fundamental security analysis, the Adviser independently analyzes each green bond it selects for the Fund along the following lines:

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Use of Proceeds: legal documentation specifies that proceeds will be used to finance or refinance projects with a positive environmental impact, such as projects relating to climate change, preservation of resources, pollution prevention or mitigation and biodiversity.

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Impact on Sustainable Opportunity: quality of the environmental impact of the project is analyzed. Four evaluation levels have been defined with respect to the positive environmental impact: High, Significant, Low or No, and Negative. Only issues that the Adviser believes will have a High or Significant positive environmental impact can qualify.

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Risk Evaluation: an analysis of the general practices of the issuer and of the management of the environmental and social risks during the life cycle of the projects.

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Reporting: issuer should provide regular reports on the use of proceeds. This reporting will also be used to reevaluate all other aspects of the Adviser's analysis as described above.

The Adviser monitors developments in the global green bond market and may revise the above criteria in the future.

In connection with its principal investment strategies, the Fund may also invest in securities issued pursuant to Rule 144A under the Securities Act of 1933 ("Rule 144A securities"), municipal securities, mortgage-related and asset-backed securities, debt-linked and equity-linked securities, hybrid instruments and futures, forwards and foreign currency transactions for hedging and investment purposes. Except as provided above or as required by applicable law, the Fund is not limited in the percentage of its assets that it may invest in these instruments. The Adviser generally attempts to hedge the Fund's foreign currency risk, though there is no guarantee its attempts to hedge all foreign currency risk will be successful.

The Fund is non-diversified, which means that it may invest a greater percentage of its assets in a particular issuer and may invest in fewer issuers. Because the Fund may invest in the securities of a limited number of issuers, an investment in the Fund may involve a higher degree of risk than would be present in a diversified portfolio.

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Fund Summary

Principal Investment Risks

The principal risks of investing in the Fund are summarized below. The Fund does not represent a complete investment program. You may lose money by investing in the Fund.

Below Investment Grade Fixed-Income Securities Risk: The Fund's investments in below investment grade fixed-income securities, also known as "junk bonds," may be subject to greater risks than other fixed-income securities, including being subject to greater levels of interest rate risk, credit/counterparty risk (including a greater risk of default) and liquidity risk. The ability of the issuer to make principal and interest payments is predominantly speculative for below investment grade fixed-income securities.

Credit/Counterparty Risk: Credit/Counterparty risk is the risk that the issuer or the guarantor of a fixed-income security, or the counterparty to a derivatives or other transaction, will be unable or unwilling to make timely payments of interest or principal or to otherwise honor its obligations. The Fund will be subject to credit risks with respect to the counterparties of its derivative transactions. Many of the protections afforded to participants on organized exchanges, such as the performance guarantee of an exchange clearinghouse, are not available in connection with over-the-counter ("OTC") derivative transactions, such as foreign currency transactions. As a result, in instances when the Fund enters into OTC derivative transactions, the Fund will be subject to the risk that its direct counterparties will not perform their obligations under the transactions and that the Fund will sustain losses or be unable to realize gains.

Currency Risk: Fluctuations in the exchange rates between different currencies may negatively affect an investment. The Fund may be subject to currency risk because it may invest in currency-related instruments and may invest in securities or other instruments denominated in, or that generate income denominated in, foreign currencies. The Fund may elect not to hedge currency risk, or may hedge such risk imperfectly, which may cause the Fund to incur losses that would not have been incurred had the risk been hedged. 

Derivatives Risk:  Derivative instruments (such as those in which the Fund may invest, including futures and forward contracts) are subject to changes in the value of the underlying assets or indices on which such instruments are based. There is no guarantee that the use of derivatives will be effective or that suitable transactions will be available. Even a small investment in derivatives may give rise to leverage risk and can have a significant impact on the Fund's exposure to commodities markets, securities markets values, interest rates or currency exchange rates. It is possible that the Fund's liquid assets may be insufficient to support its obligations under its derivatives positions. The use of derivatives for other than hedging purposes may be considered a speculative activity, and involves greater risks than are involved in hedging. The use of derivatives may cause the Fund to incur losses greater than those that would have occurred had derivatives not been used. The Fund's use of derivatives, such as futures, forward contracts and other foreign currency transactions, involves other risks, such as the credit risk relating to the other party to a derivative contract (which is greater for over-the-counter ("OTC") derivatives),  the risk of difficulties in pricing and valuation, the risk that changes in the value of a derivative may not correlate as expected with changes in the value of relevant assets, rates or indices, liquidity risk, allocation risk and the risk of losing more than the initial margin required to initiate derivatives positions. There is also the risk that the Fund may be unable to terminate or sell a derivatives position at an advantageous time or price. The Fund's derivative counterparties may experience financial difficulties or otherwise be unwilling or unable to honor their obligations, possibly resulting in losses to the Fund. 

Emerging Markets Risk: In addition to the risks of investing in foreign investments generally, emerging markets investments are subject to greater risks arising from political or economic instability, nationalization or confiscatory taxation, currency exchange restrictions, sanctions by the U.S. government and an issuer's unwillingness or inability to make principal or interest payments on its obligations. Emerging markets companies may be smaller and have shorter operating histories than companies in developed markets.

Foreign Securities Risk: Investments in foreign securities may be subject to greater political, economic, environmental, credit and information risks. The Fund's investments in foreign securities also are subject to foreign currency fluctuations and other foreign currency-related risks. Foreign securities may be subject to higher volatility than U.S. securities, varying degrees of regulation and limited liquidity.

Interest Rate Risk: Interest rate risk is the risk that the value of the Fund's investments will fall if interest rates rise.  Generally, the value of fixed-income securities rises when prevailing interest rates fall and falls when interest rates rise.  Interest rate risk generally is greater for funds that invest in fixed-income securities with relatively longer durations than for funds that invest in fixed-income securities with shorter durations.  In addition, an economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Fund's ability to sell them, negatively impacting the performance of the Fund.

Large Investor Risk: Ownership of shares of the Fund may be concentrated in one or a few large investors. Such investors may redeem shares in large quantities or on a frequent basis. Redemptions by a large investor can affect the performance of the Fund, may increase realized capital gains, may accelerate the realization of taxable income to shareholders and may increase transaction costs. These transactions potentially limit the use of any capital loss carryforwards and certain other losses to offset future realized capital gains (if any). Such transactions may also increase the Fund's expenses.

Leverage Risk: Use of derivative instruments may involve leverage.  Leverage is the risk associated with securities or practices that multiply small index, market or asset-price movements into larger changes in value. The use of leverage increases the impact of gains and losses on a fund's returns, and may lead to significant losses if investments are not successful.

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Fund Summary

Liquidity Risk: Liquidity risk is the risk that the Fund may be unable to find a buyer for its investments when it seeks to sell them or to receive the price it expects. Decreases in the number of financial institutions willing to make markets in the Fund's investments or in their capacity or willingness to transact may increase the Fund's exposure to this risk.  Events that may lead to increased redemptions, such as market disruptions or increases in interest rates, may also negatively impact the liquidity of the Fund's investments when it needs to dispose of them. If the Fund is forced to sell its investments at an unfavorable time and/or under adverse conditions in order to meet redemption requests, such sales could negatively affect the Fund. Securities acquired in a private placement, such as Rule 144A securities, are generally subject to greater liquidity risk because they are subject to strict restrictions on resale and there may be no liquid secondary market or ready purchaser for such securities. Non-exchange traded derivatives are generally subject to greater liquidity risk as well. Liquidity issues may also make it difficult to value the Fund's investments.

Management Risk: A strategy used by the Fund's portfolio managers may fail to produce the intended result.

Market/Issuer Risk: The market value of the Fund's investments will move up and down, sometimes rapidly and unpredictably, based upon overall market and economic conditions, as well as a number of reasons that directly relate to the issuers of the Fund's investments, such as management performance, financial condition and demand for the issuers' goods and services. 

Mortgage-Related and Asset-Backed Securities Risk: In addition to the risks associated with investments in fixed-income securities generally (for example, credit, liquidity and valuation risk), mortgage-related and asset-backed securities are subject to the risks of the mortgages and assets underlying the securities as well as prepayment risk, the risk that the securities may be prepaid and result in the reinvestment of the prepaid amounts in securities with lower yields than the prepaid obligations. Conversely, there is a risk that a rise in interest rates will extend the life of a mortgage-related or asset-backed security beyond the expected prepayment time, typically reducing the security's value, which is called extension risk. The Fund also may incur a loss when there is a prepayment of securities that were purchased at a premium. The Fund's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets.

Non-Diversification Risk: Compared with other mutual funds, the Fund may invest a greater percentage of its assets in a particular issuer and may invest in fewer issuers. Therefore, the Fund may have more risk because changes in the value of a single security or the impact of a single economic, political or regulatory occurrence may have a greater adverse impact on the Fund's net asset value.

Sustainable Investment Style Risk: Because the Fund focuses on bonds whose purpose is to finance projects with a positive environmental impact, its universe of investments may be smaller than that of other funds and therefore the Fund may underperform the market as a whole if such investments underperform the market. The Fund may forgo opportunities to gain exposure to certain attractive companies, industries, sectors or countries and it may choose to sell a security when it might otherwise be disadvantageous to do so. In addition, certain green bonds may be dependent on government incentives and subsidies and lack of political support for the financing of projects with a positive environmental impact could negatively impact the performance of the Fund.

Risk/Return Bar Chart and Table

Because the Fund has not yet completed a full calendar year, information related to Fund performance, including a bar chart showing annual returns, has not been included in this Prospectus. The performance information provided by the Fund in the future will give some indication of the risks of an investment in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns compare against those of a broad measure of market performance. The Fund's past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information is available online at ngam.natixis.com and/or by calling the Fund toll-free at 800-225-5478.

Management

Investment Adviser

Natixis Asset Management U.S., LLC ("Natixis AM US")

Portfolio Managers

Christopher Wigley, has served as lead portfolio manager of the Fund since 2017. 

Marc Briand, has served as portfolio manager of the Fund since 2017.

Each portfolio manager is an employee of Mirova, an affiliate of Natixis AM US, and provides portfolio management through a personnel-sharing arrangement between Mirova and Natixis AM US. 

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Fund Summary

Purchase and Sale of Fund Shares

Class A Shares

The following chart shows the investment minimums for various types of accounts:

Type of Account	Minimum Initial Purchase		Minimum Subsequent Purchase
Any account other than those listed below	$	2,500	$	100
For shareholders participating in Natixis Funds' Investment Builder Program	$	1,000	$	50
For Traditional IRA, Roth IRA, Rollover IRA, SEP-IRA and Keogh plans using the Natixis Funds' prototype document (direct accounts, not held through intermediary)	$	1,000	$	100
Coverdell Education Savings Accounts using the Natixis Funds' prototype document (direct accounts, not held through intermediary)	$	500	$	100

Class N Shares

Class N shares of the Fund are subject to a $1,000,000 initial investment minimum. There is no initial investment minimum for certain retirement plans and funds of funds that are distributed by NGAM Distribution, L.P. There is no subsequent investment minimum for these shares.

Class Y Shares

Class Y shares of the Fund may be purchased by the following entities at the following investment minimums.

A minimum initial investment of $100,000 and the minimum subsequent investment of $100 for:

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Other mutual funds, endowments, foundations, bank trust departments or trust companies.

There is no initial or subsequent investment minimum for:

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Wrap Fee Programs of certain broker-dealers, the advisers or NGAM Distribution, L.P. Please consult your financial representative to determine if your wrap fee program is subject to additional or different conditions or fees.

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Certain Retirement Plans.

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Certain Individual Retirement Accounts if the amounts invested represent rollover distributions from investments by any of the retirement plans invested in the Fund.

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Clients of a Registered Investment Adviser where the Registered Investment Adviser receives an advisory, management, or consulting fee.

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Fund Trustees, former Fund trustees, employees of affiliates of the Natixis Funds and other individuals who are affiliated with any Natixis Fund (this also applies to any spouse, parents, children, siblings, grandparents, grandchildren and in-laws of those mentioned) and Natixis affiliate employee benefit plans.

Due to operational limitations at your financial intermediary, certain wrap fee programs, retirement plans, individual retirement accounts and accounts of registered investment advisers may be subject to the investment minimums described above.

The Fund's shares are available for purchase and are redeemable on any business day through your investment dealer, directly from the Fund by writing to the Fund at Natixis Funds, P.O. Box 219579, Kansas City, MO 64121-9579, by exchange, by wire, by internet at ngam.natixis.com (certain restrictions may apply), through the Automated Clearing House system, or, in the case of redemptions, by telephone at 800-225-5478 or by the Systematic Withdrawal Plan. See section "How Fund Shares are Priced" for details.

Tax Information

Fund distributions are generally taxable to you as ordinary income or capital gains, except for distributions to retirement plans and other investors that qualify for tax-advantaged treatment under U.S. federal income tax law generally. Investments in such tax-advantaged plans will generally be taxed only upon withdrawal of monies from the tax-advantaged arrangement.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and its related companies may pay the intermediary for the sale of the Fund shares and related services. 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.

UMGG77-0217

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