Summary Prospectus by Investment Company (Form 497K)

Parametric Emerging Markets Fund

This Summary Prospectus is designed to provide investors with key fund information in a clear and concise format. Before you invest, you may want to review the Fund's Prospectus and Statement of Additional Information, which contain more information about the Fund and its risks. The Fund's Prospectus and Statement of Additional Information, both dated June 1, 2026, as may be amended or supplemented, are incorporated by reference into this Summary Prospectus. For free paper or electronic copies of the Fund's Prospectus, Statement of Additional Information, annual and semi-annual shareholder reports, and other information about the Fund, go to  http://www.eatonvance.com/ppafunddocuments, email a request to [email protected], call 1-800-260-0761, or ask any financial advisor, bank, or broker-dealer who offers shares of the Fund. Unless otherwise noted, page number references refer to the current Prospectus for this Fund.

Investment Objective

The Fund's investment objective is to seek long-term capital appreciation.

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. Investors may also pay commissions or other fees to their financial intermediary, which are not reflected below. You may qualify for a reduced sales charge on purchases of Class A shares if you invest, or agree to invest over a 13-month period, at least $50,000 in Eaton Vance  funds. Certain financial intermediaries also may offer variations in Fund sales charges to their customers as described in Appendix A - Financial Intermediary Sales Charge Variations in the Fund's Prospectus. More information about these and other discounts is available from your financial intermediary and in Sales Charges beginning on page 31 of the Fund's Prospectus and page 21  of the Fund's Statement of Additional Information.

Shareholder Fees (fees paid directly from your investment)

Parametric Emerging Markets Fund   | Fund Summary

Parametric Emerging Markets Fund (Con't)

Annual Fund Operating Expenses (expenses you pay each year as a percentage of the value of your investment)

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. The Example also assumes that your investment has a 5% return each year, that the operating expenses remain the same and that any expense reimbursement arrangement remains in place for the contractual period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Portfolio Turnover

The  Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" the 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. During the most recent fiscal year, the Fund's portfolio turnover rate was 2%  of the average value of its portfolio.

Principal Investment Strategies

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 located in emerging market countries (the "80% Policy"). A company will be considered to be located in an emerging market country if it is domiciled in and tied economically to one or more emerging market countries and may include a company's stock which is trading in the form of a depositary receipt. Emerging market countries are generally countries not considered to be developed market countries, and therefore not included in the MSCI World Index. The Fund intends to invest primarily in securities issued by companies located in countries included in the MSCI Emerging Markets Index or the MSCI Frontier Markets Index. The MSCI Emerging Markets Index is an unmanaged index of common stocks of issuers in emerging markets countries. The MSCI Frontier Markets Index is an unmanaged index of common stocks of issuers in countries that have less-developed economies and financial markets than more established emerging markets, and often have more restrictions on foreign stock ownership. Securities acquired by the Fund are typically listed on stock exchanges in emerging market countries, but also may include securities

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Parametric Emerging Markets Fund |  Fund Summary

Parametric Emerging Markets Fund (Con't)

traded in markets outside these countries. The Fund may invest in securities issued by companies with a broad range of market capitalizations, including those of smaller, less seasoned companies. More than 25% of the Fund's total assets may be denominated in any single currency. The Fund may invest in exchange-traded funds ("ETFs"), a type of pooled investment vehicle, in order to manage cash positions or seek exposure to certain markets or market sectors. The Fund may also invest in publicly traded real estate investment trusts ("REITs"). The Fund may also lend its securities.

The Fund seeks to employ a top-down, disciplined and systematic investment process that emphasizes broad exposure and diversification among emerging market countries, economic sectors and issuers. This rules-based strategy utilizes targeted allocation and systematic  rebalancing to take advantage of certain quantitative and behavioral characteristics of emerging markets identified by the portfolio managers. The investment process is periodically re-evaluated and may be adjusted to ensure that the process is consistent with the Fund's investment objective and strategies. The portfolio managers select and allocate across countries based on factors such as size, liquidity, level of economic development, local economic diversification, and perceived risk and potential for growth. The Fund maintains a bias to broad inclusion; that is, the Fund intends to allocate its portfolio holdings to more emerging market countries rather than fewer emerging market countries. Relative to capitalization-weighted country indexes, the Fund's individual country allocation targets seek to emphasize the less represented emerging market countries and attempt to reduce concentration risks relative to a capitalization-weighted index. The Fund's country allocations are typically rebalanced to their target weights if they exceed a certain pre-determined overweight or fall below a certain pre-determined underweight. Rebalancing is intended to reduce exposure to countries with strong relative performance and increasing exposure to countries which have underperformed. The frequency of rebalancing depends on the volatility and trading costs of the individual country. At the portfolio level and within each country, the Fund seeks to maintain exposure across key economic sectors. Relative to capitalization-weighted country indexes, the portfolio managers target weights to these sectors to emphasize the less represented sectors. The portfolio managers use a quantitative model to select individual securities as representatives of their economic sectors and generally weigh them by their relative capitalization within that sector.

Principal Risks

Market Risk. The value of investments held by the Fund may increase or decrease in response to social, economic, political, financial, public health crises or other disruptive events (whether real, expected or perceived) in the U.S. and global markets and include events such as war, natural disasters, epidemics and pandemics, terrorism, conflicts and social unrest. These events may negatively impact broad segments of businesses and populations and may exacerbate pre-existing risks to the Fund. The frequency and magnitude of resulting changes in the value of the Fund's investments cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in reaction to changing market conditions. Monetary and/or fiscal actions taken by U.S. or foreign governments to stimulate or stabilize the global economy may not be effective and could lead to high market volatility.

Equity Securities Risk. The value of equity securities and related instruments may decline in response to adverse changes in the economy or the economic outlook; deterioration in investor sentiment; interest rate, currency, and commodity price fluctuations; adverse geopolitical, social or environmental developments; issuer and sector-specific considerations; unexpected trading activity among retail investors; or other factors. Market conditions may affect certain types of stocks to a greater extent than other types of stocks. If the stock market declines in value, the value of the Fund's equity securities will also likely decline. Although prices can rebound, there is no assurance that values will return to previous levels.

Foreign Investment Risk. Foreign investments can be adversely affected by political, economic and market developments abroad, including the imposition of economic and other sanctions by the United States or another country against a particular country or countries, organizations, entities and/or individuals. There may be less publicly available information about foreign issuers because they may not be subject to reporting practices, requirements or regulations comparable to those to which United States companies are subject. Adverse changes in investment regulations, capital requirements or exchange controls could adversely affect the value of the Fund's investments. Foreign markets may be smaller, less liquid and more volatile than the major markets in the United States and, as a result, Fund share values may be more volatile. Trading in foreign markets typically involves higher expense than trading in the United States. The Fund may have difficulties enforcing its legal or contractual rights in a foreign country. Depositary receipts are subject to many of the risks associated with investing directly in foreign instruments, including the political and economic risks of the underlying issuer's country and, in the case of depositary receipts traded on foreign markets, currency risk.

Emerging Markets Investment Risk. Investment markets within emerging market countries are typically smaller, less liquid, less developed and more volatile than those in more developed markets like the United States, and may be focused in certain sectors. Emerging market securities often involve greater risks than developed market securities. The information available about an emerging market issuer may be less reliable than for comparable issuers in more developed capital markets. Such risks may be greater in frontier markets.

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Parametric Emerging Markets Fund   | Fund Summary

Parametric Emerging Markets Fund (Con't)

Frontier Market Investment Risk. Frontier markets are among the smallest and least mature investment markets. Frontier market countries may have greater political or economic instability and may also be subject to trade barriers, adjustments in currency values and developing or changing securities laws and other regulations. Investments in frontier market countries generally are less liquid and subject to greater price volatility than investments in developed markets or emerging markets.

China Region Risk. Economies of countries in the China region differ from the U.S. economy or other foreign (including emerging) economies in various ways, such as structure, general development, government involvement, wealth distribution, interest rates, rate of growth of gross national product, rate of inflation, capital reinvestment, resource self-sufficiency and balance of payments position. As export-driven economies, the economies of countries in the China region are affected by developments in the economies and governmental actions of their principal trading partners, such as the imposition of trading restrictions and tariffs. The Chinese central government has historically exercised substantial control over virtually every sector of the Chinese economy through administrative regulation, state ownership and/or other involvement. Actions of the Chinese central and local government authorities continue to have a substantial effect on economic conditions in China and operations of particular Chinese companies, which could adversely affect the value and liquidity of investments. For example, a government may restrict investment in companies or industries considered important to national interests, intervene in the financial markets, maintain strict currency controls, or impose repatriation restrictions. Significant portions of the Chinese securities markets may become rapidly illiquid, as Chinese issuers may suspend the trading of their equity securities. In addition, there is the potential of increased tariffs and restrictions (and threats thereof) on trade between the U.S. and China, concerns of which have been heightened (and realized) by recent developments in relations between the U.S., other trading partners and China, including the designation of China as a "foreign adversary" of the U.S., as well as countersanctions or countermeasures from the Chinese government that have been triggered or are expected to be triggered. An increase in tariffs or trade restrictions, or even the threat of such developments, could lead to a significant reduction in international trade, which could have a negative impact on China's export industry, Chinese issuers, the liquidity or price of the Fund's direct or indirect investments in China and, therefore, the Fund. The Fund's investments in Chinese securities are also subject to additional risks associated with differing regulatory and audit requirements in Chinese securities markets as compared to the U.S. securities market, including a lack of reliable audits and other financial information regarding many Chinese companies and heightened risk of market manipulation and fraud, which may be increased through actions taken by the Chinese government. In addition, the relationship between China and Taiwan is particularly sensitive, and hostilities between China and Taiwan, including continued threats by China to invade and control Taiwan, present a significant risk to the Fund's investments in China. Ongoing political tension between the People's Republic of China and the Hong Kong Special Administrative Region may have impacts on the economy of Hong Kong, and these impacts remain uncertain. Military or diplomatic moves involving China could significant adversely affect the economies and issuers in the China region and, thus, the Fund's investments. Although China and certain other countries in the China region may be larger and/or more established than many emerging markets, markets in these countries carry the high levels of risk associated with emerging markets. Investments in China involve a risk of total loss due to government action or inaction or other adverse circumstances.

Currency Risk. Exchange rates for currencies fluctuate daily. The value of foreign investments may be affected favorably or unfavorably by changes in currency exchange rates in relation to the  U.S. dollar. Currency markets generally are not as regulated as securities markets and currency transactions are subject to settlement, custodial and other operational risks.

Focused Investment Risk. To the extent the Fund has substantial investments in a relatively small number of securities or issuers, or a particular market, industry, group of industries, country, region, group of countries, asset class or sector, the Fund's performance will be more susceptible to any single economic, market, political, or regulatory occurrence affecting those particular securities or issuers or that particular market, industry, group of industries, country, region, group of countries, asset class, or sector than a fund that invests more broadly.

Geographic Risk. Because the Fund may invest significantly in a particular geographic region or country, the value of Fund shares may be affected by events that adversely affect that region or country and may fluctuate more than that of a fund that invests more broadly.

Smaller Company Risk. The stocks of smaller, less seasoned companies are generally subject to greater price fluctuations, limited liquidity, higher transaction costs and higher investment risk than the stocks of larger, more established companies. Such companies may have limited product lines, markets or financial resources, may be dependent on a limited management group, and may lack substantial capital reserves or an established performance record. There may be generally less publicly available information about such companies than for larger, more established companies. Stocks of these companies frequently have lower trading volumes making them more volatile and potentially less liquid and more difficult to value.

ETF Risk. ETFs are subject to the risks of investing in the underlying securities or other investments. ETF shares may trade at a premium or discount to net asset value and are subject to secondary market trading risks. In addition, the Fund will bear a pro rata portion of the operating expenses of an ETF in which it invests.

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Parametric Emerging Markets Fund |  Fund Summary

Parametric Emerging Markets Fund (Con't)

Liquidity Risk. The Fund is exposed to liquidity risk when trading volume, lack of a market maker or trading partner, large position size, market conditions, or legal restrictions impair its ability to sell particular investments or to sell them at advantageous market prices. Consequently, the Fund may have to accept a lower price to sell an investment or continue to hold it or keep the position open, sell other investments to raise cash or abandon an investment opportunity, any of which could have a negative effect on the Fund's performance. These effects may be exacerbated during times of financial or political stress.

Real Estate Risk. Real estate investments are subject to risks associated with owning real estate, including declines in real estate values, increases in property taxes, fluctuations in interest rates, limited availability of mortgage financing, decreases in revenues from underlying real estate assets, declines in occupancy rates, changes in government regulations affecting zoning, land use, and rents, environmental liabilities, and risks related to the management skill and creditworthiness of the issuer. Companies in the real estate industry may also be subject to liabilities under environmental and hazardous waste laws, among others. REITs  must satisfy specific requirements for favorable tax treatment and can involve unique risks in addition to the risks generally affecting the real estate industry. Changes in underlying real estate values may have an exaggerated effect to the extent that investments are concentrated in particular geographic regions or property types.

Rules-Based Management Risks. The sub-adviser uses proprietary investment techniques and analyses in making investment decisions for the  Fund, seeking to achieve its investment objective while minimizing exposure to security-specific risk. The strategy seeks to take advantage of certain quantitative and behavioral market characteristics identified by the sub-adviser, utilizing a rules-based process and systematic rebalancing. A systematic investment process is dependent on the sub-adviser's skill in developing and maintaining that process. The  Fund's strategy has not been independently tested or validated, and there can be no assurance that it will achieve the desired results.

Securities Lending Risk. Securities lending involves 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 also may lose rights in the collateral if the borrower fails financially. The Fund could also lose money if the value of the collateral decreases or if the value of any investments made with cash collateral declines.

General Fund Investing Risks. The Fund is not a complete investment program and there is no guarantee that the Fund will achieve its investment objective. It is possible to lose money by investing in the Fund. The Fund is designed to be a long-term investment vehicle and is not suited for short-term trading. Investors in the Fund should have a long-term investment perspective and be able to tolerate potentially sharp declines in value. Purchase and redemption activities by Fund shareholders may impact the management of the Fund and its ability to achieve its investment objective(s). In addition, the redemption by one or more large shareholders or groups of shareholders of their holdings in the Fund could have an adverse impact on the remaining shareholders in the Fund. The Fund relies on various service providers, including the investment adviser and sub-adviser, if applicable, in its operations and is susceptible to operational, information security and related events (such as public health crises, cyber or hacking attacks) that may affect the service providers or the services that they provide to the Fund. An investment in the Fund is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Performance

The following bar chart and table provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and how the Fund's average annual returns over time compare with those of a broad-based securities market index. The returns in the bar chart are for Class A shares and do not reflect a sales charge. If the sales charge was reflected, the returns would be lower. Past performance (both before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Effective April 29, 2022, the Fund's Investor Class shares were redesignated as Class A shares and the Fund's Institutional Class shares were redesignated as Class I shares. The Fund's performance for certain periods reflects the effects of expense reductions. Absent these reductions, performance for certain periods would have been lower. Updated Fund performance information can be obtained by visiting www.eatonvance.com.

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Parametric Emerging Markets Fund   | Fund Summary

Parametric Emerging Markets Fund (Con't)

During the period shown in the bar chart above:

The year-to-date total return through the end of the most recent calendar quarter (December 31, 2025 to March 31, 2026) was 2.89%.

Average Annual Total Return (for the calendar periods ended December 31, 2025)

These returns reflect the maximum current sales charge for Class A (5.25%) and any applicable contingent deferred sales charge ("CDSC") for Class C. Effective November 5, 2020, Class C shares automatically convert to Class A shares eight years after purchase. The average annual total returns listed for Class C reflect conversion to Class A shares after eight years. Prior to November 5, 2020, Class C shares automatically converted to Class A shares ten years after purchase. On April 29, 2022, the Fund's Investor Class shares were redesignated as Class A shares and the Fund's Institutional Class shares were redesignated as Class I shares. Investor Class shares had previously been sold without a sales charge. Investors cannot invest directly in an Index.

Source for  MSCI Emerging Markets Index: MSCI. MSCI data may not be reproduced or used for any other purpose.  MSCI provides no warranties, has not prepared or approved this report, and has no liability hereunder.  

After-tax returns are calculated using the highest historical individual U.S. federal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on a shareholder's tax situation and the actual characterization of distributions, and may differ from those shown. After-tax returns are not relevant to shareholders who hold shares in tax-deferred accounts or to shares held by non-taxable entities. After-tax returns for other Classes of shares will vary from the after-tax returns presented for Class A shares.  Return After Taxes on Distributions for a period may be the same as Return Before Taxes for that period because no taxable distributions were made during that period. Also, Return After Taxes on Distributions and Sale of Fund Shares for a period may be greater than or equal to Return Before Taxes and/or Return After Taxes on Distributions for the same period because of losses realized on the sale of Fund shares.

Management

Investment Adviser. Eaton Vance Management ("Eaton Vance").

Investment Sub-Adviser. Parametric Portfolio Associates LLC ("Parametric").

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Parametric Emerging Markets Fund |  Fund Summary

Parametric Emerging Markets Fund (Con't)

Portfolio Managers

Purchase and Sale of Fund Shares

You may purchase, redeem or exchange Fund shares on any business day, which is any day the New York Stock Exchange is open for business. Class C shares are not available for purchase, except by: (1) existing shareholders (including shares acquired through the reinvestment of dividends and distributions); or (2) employer sponsored retirement plans. You may purchase, redeem or exchange Fund shares either through your financial intermediary or (except for purchases of Class C shares by accounts with no specified financial intermediary) directly from the Fund either by writing to the Fund, P.O. Box 534439, Pittsburgh, PA 15253-4439, or by calling 1-800-260-0761. The minimum initial purchase or exchange into the Fund is $1,000 for Class A and Class C, $1,000,000 for Class I and $5,000,000 for Class R6 (waived in certain circumstances). There is no minimum for subsequent investments.

Tax Information

If your shares are held in a taxable account, the Fund's distributions will be taxed to you as ordinary income and/or capital gains, unless you are exempt from taxation. If your shares are held in a tax-advantaged account, you will generally be taxed only upon withdrawals from the account.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase the Fund's shares through a broker-dealer or other financial intermediary (such as a bank) (collectively, "financial intermediaries"), the Fund, its principal underwriter and its affiliates may pay the financial intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the financial intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.