The Proxy Statement will be mailed on or about March 12, 2020 to shareholders of record of the Walden Small Cap Fund as of February 10, 2020 (the "Record Date").

Important Notice Regarding Internet Availability of Proxy Materials

This Proxy Statement is available at www.btim.com.https:/www.bostontrustwalden.com/ investment-services/mutual-fund/. The Trust’sTrust's Proxy Statement and annual and semi-annual reportsAnnual Reports are available at no charge by calling [1-800-282-8782 x7050].1-800-282-8782 ext.7050.

TABLE OF CONTENTS

SUMMARY

The following is a summary of information contained elsewhere in this Proxy Statement and is qualified in its entirety by references to the more complete information contained herein. Shareholders should read the entire Proxy Statement carefully.

2The Trust, organized under the laws of the Commonwealth of Massachusetts, is an open-end management investment company registered with the SEC. The Trust consists of multiple series, including the Boston Trust Walden Small Cap Fund (the "Survivor Fund") and the Walden Small Cap Fund (the "Target Fund"). The investment goal of both the Survivor Fund and the Target Fund (collectively, the "Funds") is to seek long-term capital growth through an actively managed portfolio of stocks of small capitalization ("small cap") companies. Boston Trust Walden Inc. (the "Adviser") is the investment adviser for the Funds and will continue to serve as the investment adviser for the Survivor Fund. Kenneth Scott is the lead portfolio manager, and Leanne Moore and Richard Williams are co-portfolio managers, for the Funds. They will serve as lead portfolio and co-portfolio managers, respectively, of the Survivor Fund following the Reorganization.

The Reorganization

The Reorganization. The Board, including the Trustees who are not "interested persons" of the Trust as that term is defined in the Investment Company Act of 1940 (the "Independent Trustees"), on behalf of each Fund, approved the Agreement and Plan of Reorganization (the "Plan"). The Plan provides that, if the Reorganization is completed, the Survivor Fund will acquire substantially all of the assets and the liabilities of the Target Fund, and shareholders of the Target Fund will receive shares of the Survivor Fund with an aggregate net asset value equal to the aggregate net asset value of the Target Fund shares that the shareholders own immediately prior to the Reorganization. The Target Fund will then terminate as a separate series of the Trust.

Background and Reasons for the Reorganization. The Adviser proposed the Reorganization because the Target Fund and the Survivor Fund have identical investment goals, investment strategies, portfolio management team, and management fees. Rather than operate two smaller Funds, the Adviser believes it is in the best interest of shareholders to combine the Funds because the larger Survivor Fund has better prospects for attracting assets and achieving economies of scale.

In approving the Plan, the Board, including the Independent Trustees, engaged in a thorough review process relating to the Reorganization. The Board approved the Reorganization at a meeting held on December 6, 2019. The factors considered by the Board regarding the Reorganization included, but were not limited to, the following:

•  The Reorganization is expected to improve the Survivor Fund's prospects for attracting assets. The larger net asset size is anticipated to lead to operating efficiencies and reduced costs. Ongoing regulatory, audit, operational and legal costs, for example, will likely be reduced;

•  With additional assets, the Survivor Fund will have an increased likelihood of greater stability and long-term viability;

•  The Reorganization is not expected to result in any tax consequence to Target Fund shareholders;

PROPOSALS 1-2•  Shareholders of the Target Fund will remain invested in an open-end fund with an identical investment strategy;

•  The Funds and their shareholders will not bear any of the costs of the Reorganization; and

APPROVE AMENDMENTS TO

CERTAIN FUNDAMENTAL POLICIES OF EACH FUND

•  Target Fund shareholders will receive Survivor Fund shares with the same aggregate net asset value as their Target Fund shares.

The Board, on behalfincluding all of the Trust, has approvedIndependent Trustees, concluded, based upon these factors and determinations summarized above, that completion of the filingReorganization is in the best interests of each Fund and that the interests of the Target Fund and Survivor Fund shareholders will not be diluted as a result of the Reorganization.

Investment Goals and Principal Investment Strategies

The Funds have identical investment goals and investment strategies. See "Comparison of the Target Fund and the Survivor Fund — Comparison of Investment Goals and Principal Investment Strategies" below.

Investment Goals

Each Fund's investment goal is to seek long-term capital growth through an actively managed portfolio of stocks of small capitalization ("small cap") companies.

Investment Strategies

Each Fund invests, under normal circumstances, at least 80% of its assets in a diversified portfolio of domestic equity securities of small cap companies. Equity securities include common stock and any rights to purchase common stock. "Assets" means net assets, plus the amount of borrowing for investment purposes. The Adviser defines small cap issuers as those with market capitalizations within the range encompassed by the Russell 2000^® Index at the time of purchase. The size of companies in the Russell 2000^® Index may change with market conditions. In addition, changes to the composition of the Russell 2000^® Index can change the market capitalization range of the companies included in the index. As of [ ], 2019, the market capitalization range of the Russell 2000^® Index was between $[ ] million and $[ ] billion.

The Adviser evaluates financially material environmental, social, and governance (ESG) factors as part of the investment decision-making process for the Funds. The Adviser considers financial materiality as it is understood in generally accepted accounting principles — information that would impact the judgment of an applicationinformed investor. The Adviser's ESG analysis considers the range of impacts that ESG factors may have on future revenues, expenses, assets, liabilities and overall risk. Both Funds are subject to the same screening criteria in which the Adviser excludes companies with significant exposure in specific products or services, considering their revenue dependence (share of total revenue derived from undesirable products/services), market share (if a company is a market leader in an undesirable product despite relatively small share of total company revenue), and

severity (how proximate is the product or service to the undesirable product — e.g., minor electronic input to a weapon system). "Significant exposure" is not expressed as a numerical percentage or dollar value, but rather is a subjective determination made after considering a company's revenue dependence, market share and leadership, and the specific nature of the product or services and its importance and proximity to the excluded areas. In addition, the Adviser utilizes active ownership to encourage more sustainable business policies and practices and greater ESG transparency. The Adviser encourages portfolio companies to improve their ESG performance and transparency through shareholder engagement. Engagement strategies include proxy voting, dialogue with company management, sponsorship of shareholder resolutions, and public policy advocacy.

The Target Fund and the Survivor Fund invest in the same companies. As a result, the Adviser does not anticipate selling any investments in connection with the Reorganization. For information on risks, see "Comparison of the Target Fund and Survivor Fund — Risks of the Funds," below. The fundamental investment policies applicable to each Fund are identical.

Federal Tax Consequences

It is expected that the Reorganization itself will be a tax-free reorganization under Section 368(a) of the Internal Revenue Code of 1986, as amended (the “Application”"Code"). Accordingly, no gain or loss is expected to be recognized by the Funds or their shareholders as a direct result of the Reorganization. Dividends and other distributions will be distributed to Target and Survivor Fund shareholders prior to the Reorganization. Consistent with market practice, the Trust will have received on April 3, 2020, an opinion of counsel to the effect that the Reorganization should qualify as a tax-free reorganization for federal income tax purposes as defined by Section 368(a) of the Code.

Purchase, Exchange, Redemption, Transfer and Valuation of Shares

The policies of the Target Fund and the Survivor Fund regarding the purchase, redemption, exchange, transfer, and valuation of shares are identical. Please refer to the section "Comparison of the Target Fund and Survivor Fund — Purchase, Redemption, and Pricing of Fund Shares" in this Combined Prospectus/Proxy Statement for more detail.

Principal Risks

Because of their identical investment strategies, the following primary risks are associated with an order (the “Order”)investment in each Fund:

Market Risk: Market risk refers to the risk related to investments in securities in general and the daily fluctuations in the securities markets.

Equity Risk: The value of the equity securities held by the Fund, and thus the value of the Fund's shares, can fluctuate — at times dramatically.

Small Cap Company Risk: These companies may be subject to greater market risks and fluctuations in value than large capitalization companies and may not correspond to changes in the stock market in general.

Management Risk: The Adviser's judgments about the attractiveness, value, and potential appreciation of a particular asset class or individual security in which the Fund invests may prove to be incorrect and there is no guarantee that the Adviser's judgment will produce the desired results.

ESG Criteria Risk: Because the Fund's criteria exclude securities of certain issuers for nonfinancial reasons, the Fund may forgo some market opportunities available to funds that do not use these criteria.

Fees and Expenses

As an investor, shareholders pay fees and expenses to buy and hold shares of the Funds. The following tables allow you to compare the shareholder fees and annual fund operating expenses as a percentage of the aggregate daily net assets of each Fund. The Annual Fund Operating Expenses table and Example tables shown below are based on actual expenses incurred during the fiscal year ended December 31, 2019. The "Survivor Fund After Reorganization" columns show expenses of the Survivor Fund as if the Reorganization had occurred on the last day of the fiscal year ended December 31, 2019. Please keep in mind that, as a result of changing market conditions, total asset levels, and other factors, expenses at any time during the current fiscal year may be significantly different from those shown.

Shareholder Fees (fees paid directly from your investment):

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the Securities and Exchange Commission (“SEC”) permittingvalue of your investment):

⁽¹⁾  The Adviser has entered into an Expense Limitation Agreement with each Fund to reduce fees payable to the Adviser and/or reimburse the Funds to limit the Total Fund Operating Expenses of each Fund to 1.00% of its average daily net assets through May 1, 2020 (exclusive of brokerage costs, interest, taxes, dividends, litigation expenses, indemnification, expenses associated with the investments in underlying investment companies and extraordinary expenses (as determined under generally accepted accounting principles)). The Adviser may seek recoupment of fees waived and expenses reimbursed within three years after the expenses occurred if a Fund is able to make the repayment without exceeding the current limitation on Total Fund Operating Expenses, or the limitation in place at the time of initial waiver/reimbursement. The expense limitation agreement may be terminated by the Board of Trustees at any time and will terminate automatically upon termination of the Investment Management Agreement.

EXAMPLE

This Example is intended to help you compare the cost of investing in the Funds. The example assumes that you invest $10,000 in a Fund for the time periods indicated and then redeem or continue to hold all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that each Fund's operating expenses remain the same. The example further assumes that the expense limitations of the Funds described in the footnotes to the fee table are in effect only until the end of the 1-year period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

The Management Fee for each of the Target Fund and Survivor Fund is 0.75% of the respective Fund's average daily net assets. Neither Fund assesses a Distribution and/or Service (12b-1) Fee. The Other Expenses and the gross Total Annual Fund Operating Expenses for the Survivor Fund, after the Reorganization, are anticipated to be lower than those of the Target Fund. The Surviving Fund's net Total Annual Operating Expenses after the Reorganization will be the same as before the Reorganization due to the Expense Limitation Agreement currently in place. However, the larger size of the Surviving Fund after the Reorganization may help it to attract assets, which in turn is expected to further reduce operating expenses.

Portfolio Turnover

Each 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. These costs, which are not reflected in annual fund operating expenses or in the example, affect a Fund's performance. During the most recent fiscal year, the Target Fund's portfolio turnover rate was 22.88% of the average value of its portfolio, and the Survivor Fund's portfolio turnover rate was 23.23% of the average value of its portfolio.

COMPARISON OF THE TARGET FUND AND SURVIVOR FUND

Investment Goals and Principal Investment Strategies

Each Fund's investment goal is to seek long-term capital growth through an actively managed portfolio of stocks of small capitalization ("small cap") companies. The Funds have identical principal investment strategies as shown below.

Comparison of Investment Goals and Principal Investment Strategies

The table below compares the investment goals and principal investment strategies of the two Funds:

Fundamental Investment Policies

Each Fund's fundamental investment policies and limitations, which may be changed only with the consent of shareholders, are identical except with respect to borrowing and lending. Both Funds can lend up to 33 1/3% of their total assets. However, the Target Fund may participate in anthe Trust's interfund lending facility (the “Facility”) underprogram, which permits the Funds may directlyTarget Fund to lend to and borrow money from each otheranother series of the Trust for temporary purposes, provided thatsuch as when the loans are made in accordance withcash position of the termsborrowing series is insufficient to meet temporary cash requirements. The Surviving Fund, however, may not lend money to or borrow from another series. Neither the Adviser nor the Trustees believe this policy difference is material. The Trustees believe interfund lending benefits both the lending fund and conditions set forththe borrowing fund in the Order. Withoutform of a more favorable rate of interest than a lending fund or borrowing fund would otherwise receive or pay, respectively. However, the relief provided by the Order, certain provisionsTrust uses other equally effective means of the Investment Company Act of 1940, as amended (the “1940 Act”), would prohibit the Funds from borrowing from and lending to each other under the Facility.

Currently, the Funds may invest their daily cash balances in money market funds and other short-term investments with banks or other lenders, or they may borrow money from banks or other lenders for temporary purposes to satisfy redemption requests or for other temporary purposes.  If the Order is granted, the Funds would be permitted to lend money directly to, and borrow money directly from, each other for temporary purposes (loans made under the Facility must be paid within seven days). Through the use of the Facility, the Funds intend to: (i) reduce the costs that would be incurred in borrowing from banks and other lenders; (ii) enhance their ability to earn higher interest rates on their otherwise uninvested cash balances that would be available from such short-term investments; and (iii) improve their liquidity.

Currently, the Funds are each subject to a number of “fundamental” investment restrictions, and under the 1940 Act, a fundamental investment restriction may be changed or eliminated only with shareholder approval. Two of the Funds’ fundamental investment restrictions, which relate to each Fund’s abilities to make loans and borrow money, would prohibit the Funds’ from being able to participatemanaging redemptions in the FacilitySurviving Fund, such as contemplated in the Application, even if the Order were granted.

Proposals 1redemptions-in-kind. Both interfund lending and 2, therefore, are being proposed to modify those two fundamental investment restrictions so that the Funds may, once the Order is granted, directly lend to and borrow money from each other under the Facility.

The proposed amendments to the Funds’ fundamental investment restrictions will not affect any Fund’s investment goal or its current principal investment strategies.  The Board and the Adviser anticipate that the proposed changes in the investment restrictions will not materially change the manner in which the Funds are currently managed and operated.  Although the proposed amendments will permitredemption in-kind allow the Funds to participate in the Facility, the Board and the Adviser at this time do not anticipate that the changes, individually or in the aggregate, will result inavoid selling portfolio securities to finance redemptions. Below is a material change in the current level of investment risk associated with an investment in any Fund.

Shareholders in each Fund will vote separately on Proposals 1 and 2.  If Proposals 1 and 2 are approved by the shareholders of a Fund, the changes will be effective for that Fund as of the date that shareholders are notified that the changes will be made through either (i) a supplement to the prospectus and/or Statement of  Additional Information (“SAI”) or (ii) revisions to such

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This limitation also does not preclude a Fund from investing in mortgage-related securities or investing in companies engaged in the real estate business or that have a significant portion of their assets in real estate, including real estate investment trusts.

3.  Purchase or sell commodities or commodity contracts except as may be permitted by the Investment 1940 Act or unless acquired as a result of ownership of securities or other investments. This limitation does not preclude a Fund from purchasing, selling and entering into financial futures contracts (including futures contracts on indices of securities, interest rates and currencies), options on financial futures contracts (including futures contracts on indices of securities, interest rates and currencies), warrants, swaps, forward contracts, foreign currency spot and forward contracts or other derivative instruments, including derivatives related to physical commodities; or purchasing or selling securities or other instruments backed by commodities; or purchasing or selling securities of companies that are engaged in a commodities business or have a significant portion of their assets in commodities.

4.  Invest more than 25% of the value of its net assets in the securities of companies engaged in any particular industry or group of industries, except as permitted by the SEC. This restriction does not apply to investments in securities issued or guaranteed by the U.S. government or any of its agencies or instrumentalities or repurchase agreements secured thereby.

5.  Will not issue senior securities. This limitation is not applicable to activities that may be deemed to involve the issuance or sale of a senior security by a Fund, provided that the Fund's engagement in such activities is consistent with or permitted by the 1940 Act the rules and regulations promulgated thereunder or interpretations of the SEC or its staff.

6.  Purchase the securities of any issuer, if as a result more than 5% of the total assets of the Funds would be invested in the securities of that issuer, other than obligations of the U.S. Government, its agencies or instrumentalities, provided that up to 25% of the value of the Funds' assets may be invested without regard to this limitation.

Risks of the Funds

The proposedfollowing principal and non-principal investment restrictionrisks apply to each Fund:

Market Risk: Market risk refers to the risk related to investments in securities in general and the daily fluctuations in the securities markets. The Fund's performance per share will change daily based on many factors, including fluctuation in interest rates, the quality of the instruments in the Fund's investment portfolio, national and international economic conditions and general market conditions.

Equity Risk: The value of the equity securities held by the Fund, and thus the value of the Fund's shares, can fluctuate — at times dramatically. The prices of equity securities are affected by various factors, including market conditions, political and other events, and developments affecting the particular issuer or its industry or geographic sector. When the value of the Fund's investments goes down, your investment in the Fund decreases in value and you could lose money.

Small and Mid Cap Company Risk: Investments in small, smid, and mid cap companies involve greater risks than investments in larger, more established companies. Small, smid, and mid cap companies may experience higher growth rates and higher failure rates than do larger capitalization companies. In addition, small, smid, and mid cap companies may be more vulnerable to economic, market and industry changes. As a result, share price changes may be more sudden or erratic than the prices of other equity securities, especially over the short term. The trading volume of securities of small, smid, and mid cap companies is substantiallynormally less than that of larger capitalization companies, and therefore may disproportionately affect their market price, tending to make them rise more in response to buying demand and fall more in response to selling pressure than is the samecase with larger capitalization companies.

Some small, smid, and mid cap stocks may be less liquid, making it difficult for the Fund to buy and sell shares of smaller companies. Small, smid, and mid cap companies may lack depth of management, may have limited product lines, may be unable to generate funds necessary for growth or development, or may be developing or marketing new products or services for which markets are not yet established and may never become established. Small, smid, and mid cap companies may be particularly affected by interest rate increases, as they may find it more difficult to borrow money to continue or expand operations, or may have difficulty in repaying any loans that have a floating interest rate.

Management Risk: The Adviser's judgments about the Funds’attractiveness, value, and potential appreciation of a particular asset class or individual security in which the Fund invest may prove to be incorrect and there is no guarantee that the Adviser's judgment will produce the desired results.

ESG Criteria Risk: Because the Fund's criteria exclude securities of certain issuers for nonfinancial reasons, the Fund may forgo some market opportunities available to funds that do not use these criteria.

Credit Risk: Credit risk refers to the risk related to the credit quality of the issuer of a security held in the Fund's portfolio. The Fund could lose money if the issuer of a security is unable to meet its financial obligations or the market's perception of the issuer not being able to meet those increases.

Convertible Security Risk: The market value of convertible securities and other debt securities tends to fall when prevailing interest rates rise. The value of convertible securities also tends to change whenever the market value of the underlying common or preferred stock fluctuates.

Currency Risk: The value of foreign currencies relative to the U.S. dollar fluctuates in response to market, economic, political, regulatory, geopolitical or other conditions. There is the risk that the value of such assets and/or the value of any distributions from such assets may decrease if the currency in which such assets are priced or in which they make distributions falls in relation to the value of the U.S. dollar. The Fund is not required to hedge their foreign currency risk, although it may do so through foreign currency exchange contracts and other methods. Therefore, to the extent the Fund does not hedge its foreign currency risk, or the hedges are ineffective, the value of the Fund's assets and income could be adversely affected by currency exchange rate movements.

Foreign Investment Risk: Foreign investing involves risks not typically associated with U.S. investments. These risks include, among others, adverse fluctuations in foreign currency values as well as adverse political, regulatory, social and economic developments affecting a foreign country. In addition, foreign investing involves less publicly available information, and more volatile or less liquid securities markets. Investments in foreign countries could be affected by factors not present in the U.S., such as restrictions on receiving the investment proceeds from a foreign country, foreign tax laws, and potential difficulties in enforcing contractual obligations. Foreign accounting may be less transparent than U.S. accounting practices and foreign regulation may be inadequate or irregular. Owning foreign securities could cause the Fund's performance to fluctuate more than if it held only U.S. securities. The Fund's investments in foreign securities may also be subject to foreign withholding and/or other taxes, which would decrease the Fund's yield on those securities. The potential departure of one or more countries from the European Union may have significant political and financial consequences of global markets. Uncertainty relating to the withdrawal procedures and timeline may have adverse effects on valuations and the renegotiation of current restriction, excepttrade agreements, as well as an increase in financial regulation in such markets. This may adversely impact Fund performance.

Government Risk: The U.S. government's guarantee of ultimate payment of principal and timely payment of interest on certain U.S. government securities owned by the Fund do not imply that it also permits borrowing underthe Fund's shares are guaranteed or that the price of the Fund's shares will not fluctuate. If a U.S. government agency or instrumentality in which the Fund invests defaults and the U.S. government does not stand behind the obligation, the Fund's share prices or yields could fall.

Interest Rate Risk: Interest rate risk refers to the risk that the value of the Fund's fixed-income securities can change in response to changes in prevailing interest rates causing volatility and possible loss of value. If rates increase, the value of the Fund's fixed income securities generally declines. On the other hand, if rates fall, the value of the fixed income securities generally increases. Your investment will decline in value if the value of the Fund's investments decreases. While interest rates have increased recently, they remain low by historical standards and may rise further. Consequently, the risks associated with rising interest rates are heightened. Securities with greater interest rate sensitivity, and longer maturities tend to produce higher yields, but are subject to greater fluctuations in value.

Performance History

The accompanying bar chart and table provide some indication of the risks of investing in the Funds. They show changes in each Fund's performance from year to year and how each Fund's average annual returns for the one, five, and ten-year periods compare with those of a broad-based securities market index. You should be aware that each Fund's past performance (before and after taxes) may not be an interfund lending programindication of how the Fund will perform in accordance withthe future.

To obtain performance information up to the most recent month end, call toll free (800) 282-8782, ext. 7050.

Target Fund

Annual Total Return
For Calendar Years Ended December 31

Performance Table
Average Annual Total Returns
For periods ended December 31, 2019

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Survivor Fund

Annual Total Return
For Calendar Years Ended December 31

Performance Table
Average Annual Total Returns
For periods ended December 31, 2019

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

The accounting survivor of the Reorganization will be the Survivor Fund. As such, the performance history of the Survivor Fund will continue after the Reorganization.

Management of the Funds

Adviser

Boston Trust Walden Inc., a Massachusetts corporation, serves as investment adviser to each Fund. The Adviser has been an investment adviser to mutual funds since 2001. The Adviser has managed each Fund since its inception. As of December 31, 2019, the Adviser managed approximately $2,397 million in client assets. The Adviser maintains its principal offices at One Beacon Street, Boston, MA 02108.

Under the terms of its investment advisory agreement, the Adviser is responsible for formulating each Fund's investment program and conditions of the Order.  Those termsfor making day-to-day investment decisions and conditions are anticipated to impose specific limitations on the duration, ratesengaging in portfolio transactions. The Adviser also furnishes officers, provides office space, services and amounts of loans made under the Facility that are designed to reduce the risk of borrowingequipment and provide more favorable interest rates than would otherwise be available. Those terms and conditions are anticipated to provide for substantial administrative oversight by the Board, the Trust’s CCO, the Funds’ independent public accounting firm, and the Adviser. Therefore, adoption of the proposed investment restriction is not expected to introduce additional material risksupervises all matters relating to the Funds orFunds' operations.

Pursuant to affect the ways the Funds are managed.

The Board unanimously recommends that shareholders ofinvestment advisory agreement, each Fund vote “FOR” Proposal 2.

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Mr. Williams is a Portfolio Manager at the Adviser. He joined the Adviser's parent company, of the Adviser, and has served in that role since August 2004.  As Director of ESG research, she oversees the evaluation of existing and potential securities relative to environmental, social and governance (ESG) factors.

Trustee Trust Ownership

Some of the Trustees own shares of the Funds.  The following table shows the dollar range of the shares beneficially owned by each Trustee as of [                ]:

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Shares of each Fund may be purchased from the Funds' transfer agent or through investment representatives who may charge additional fees and may require higher minimum investments or impose other limitations on buying and selling shares.

The minimum initial investment in each Fund is $100,000. Subsequent investments in the Funds must be at least $1,000. Shares of the Funds are offered continuously for purchase at the NAV per share of the Fund next determined after a purchase order is received. Investors may purchase shares of the Funds by check or wire.

Each Fund or the Adviser may waive its minimum purchase requirement, or a Fund may reject a purchase order, if it is deemed to be in the best interest of either the Fund and/or its shareholders.

Frequent Trading Policy

Frequent trading into and out of a Fund can have adverse consequences for that Fund and for long-term shareholders in the Fund. The Funds believe that frequent or excessive short-term trading activity by shareholders of a Fund may be detrimental to long-term shareholders because those activities may, among other things: (a) dilute the value of shares held by long-term shareholders; (b) cause the Funds to maintain larger cash positions than would otherwise be necessary; (c) increase brokerage commissions and related costs and expenses; and (d) incur additional tax liability. The Funds discourage frequent purchase and redemptions by shareholders and they do not make any effort to accommodate this practice. To protect against such activity, the Board has adopted policies and procedures that are intended to permit the Funds to curtail frequent or excessive short-term trading by shareholders. Both Funds reserve the right, however, to impose certain limitations at any time with respect to trading in shares of the Funds, including suspending or terminating trading privileges in Fund shares, for any investor whom the Funds believe has a history of abusive trading or whose trading, in the judgment of the Funds, has been or may be disruptive to the Funds. The Funds' ability to detect and prevent any abusive or excessive short-term trading may be limited to the extent such trading involves Fund shares held through omnibus accounts of a financial intermediary.

Investment representatives maintaining omnibus accounts with the Funds may impose market timing policies that are more restrictive than the market timing policy adopted by the Board of Trustees. For instance, these financial intermediaries may impose limits on the number of purchase and sale transactions that an investor may make over a set period of time and impose fees or penalties for transactions in excess of those limits. Investment representatives also may exempt certain types of transactions from these limitations.

In accordance with Rule 22c-2 under the Investment Company Act of 1940, the Funds have entered into information sharing agreements with certain financial intermediaries. Under these agreements, a financial intermediary is obligated to furnish the Trust, upon its request, with information regarding customer trading activities in shares of the Funds and enforce Funds' market-timing policy with respect to customers identified by the Funds as having engaged in market timing. When information regarding transactions in Fund shares is requested by the Trust and such information is in the possession of a person that is itself a financial

intermediary to a financial intermediary (an "indirect intermediary"), any financial intermediary with whom the Funds has an information sharing agreement is obligated to obtain transaction information from the indirect intermediary or, if directed by the Funds, to restrict or prohibit the indirect intermediary from purchasing shares of the Funds on behalf of other persons.

Distribution and Shareholder Services Agreements

Each Fund has adopted an identical plan under which it may enter into a Shareholder Services Agreement pursuant to which the Fund is authorized to make payments to certain entities which may include investment advisers, banks, trust companies, retirement plan administrators, and other types of service providers which provide administrative services with respect to shares of the Fund attributable to or held in the name of the service provider for its clients or other parties with whom they have a servicing relationship. Under the terms of each Shareholder Services Agreement, each Fund is authorized to pay a service provider (which may include affiliates of the Funds) a shareholder services fee which is based on the average daily net asset value of the shares of the Fund attributable to or held in the name of the service provider for providing certain administrative services to Fund shareholders with whom the service provider has a servicing relationship.

Foreign Investors

Each Fund will only accept new account applications and additional purchases of Fund shares from an established shareholder account that (1) reflects a residential address for an individual (or the principal underwriter.place of business for an entity) located within the U.S. or its territories; or (2) reflects a U.S. military address; and (3) in every case, is associated with a valid U.S. taxpayer identification number. Funds are only offered for sale in the United States and are not widely available outside the United States. Non-U.S. investors should be aware that U.S. withholding and estate taxes and certain U.S. tax reporting requirements may apply to any investment in Boston Trust Walden Funds as a U.S. mutual fund.

SELLING FUND SHARES

The procedures for redeeming the Target Fund's and Survivor Fund's shares are identical.

Selling Shares

Shares of each Fund may be redeemed at any time. The sales price will be the next NAV after a redemption request in good order is received by the Funds, their transfer agent, or the shareholder's investment representative. Normally the Funds will send proceeds, by check or electronic transfer, within seven (7) days after the request is received. The Funds typically expect to pay redemptions from cash, cash equivalents, proceeds from the sale of Fund shares, any lines of credit, and then from the sale of portfolio securities. These redemption payment methods will be used in regular and stressed market conditions.

Selling shares in each Fund may result in a realized capital gain or loss, which is subject to federal income tax. For individuals, any long-term capital gains realized from selling Fund shares currently are taxed at a maximum rate of 20%. Short-term capital gains are taxed at ordinary income tax rates. If you redeem Fund shares for

a loss, you may be able to use this capital loss to offset any other capital gains you have. An exchange of shares is considered a sale, and gains from any sale or exchange may be subject to applicable taxes.

Redemption in Kind

Each Fund reserves the right to make payment in securities rather than cash, known as "redemption in kind." This could occur under extraordinary circumstances, such as a very large redemption that could affect Fund operations (a redemption of more than 1% of a Fund's net assets). To the extent feasible, each Fund expects that a redemption in kind would be a pro rata allocation of the Fund's portfolio.

Closing of Small Accounts

Each Fund may close a shareholder account or ask a shareholder to increase the balance if the value of the account falls below $50,000 due to redemption activity. If it is still below $50,000 after 60 days, each Fund may close the account and send the shareholder the proceeds at the then current NAV.

EXCHANGING FUND SHARES

Each Fund permits shareholders to exchange shares in one Fund for shares of another series of the Trust. No transaction fees are charged for exchanges.

DIVIDENDS AND DISTRIBUTIONS

The dividend and distribution policies for the Target Fund and the Survivor Fund are identical. Any income a Fund receives in the form of dividends is paid out, less expenses, to its shareholders. Income dividends and capital gains distributions on the Funds usually are paid annually and are automatically reinvested in additional shares of the Fund at the applicable NAV on the distribution date unless you request cash distributions on your application or through a written request.

Taxations of Dividends and Distributions

The tax treatment of the Funds is identical. Dividends generally are taxable as ordinary income. Distributions designated by both Funds as long-term capital gain distributions will be taxable at long-term capital gains rate. Dividends are taxable in the year they are paid or credited to your account. However, dividends declared in October, November or December to shareholders of record in such a month and paid by January 31st are taxable on December 31st of the year they are declared.

Individual taxpayers are subject to a maximum federal income tax rate of 20% on long-term gains and from certain qualifying dividends on corporate stock. These rate reductions do not apply to corporate taxpayers. The following are guidelines for how certain distributions by the Funds are generally taxed to individual taxpayers: (i) distributions of earnings from qualifying dividends and qualifying long-term capital gains will be taxed at a maximum federal income tax rate of 20%; (ii) a shareholder will also have to satisfy a greater than 60-day holding period with respect to any distributions of qualifying dividends in order to obtain the benefit of the lower tax rate; and (iii) distributions of earnings from non- qualifying dividends, interest income, other types of ordinary income and short-term capital gains will be taxed at the ordinary income tax rate applicable to the taxpayer.

If you are a taxable investor and invest in a Fund shortly before it makes a capital gain distribution, some of your investment may be returned to you in the form of a taxable distribution. Fund distributions will reduce a Fund's NAV per share. Therefore, if you buy shares after the Fund has experienced capital appreciation but before the record date of a distribution of those gains, you may pay the full price for the shares and then effectively receive a portion of the purchase price back as a taxable distribution. This is commonly known as "buying a dividend."

You will be notified in January each year about the federal tax status of distributions made by the Funds. Depending on your state of residence, distributions also may be subject to state and local taxes, including withholding taxes. There is a penalty on certain pre- retirement distributions from retirement accounts. Consult your tax adviser about the federal, state and local tax consequences in your particular circumstances.

Foreign shareholders may be subject to special withholding requirements.

The Funds may be subject to foreign taxes or tax withholding on dividends, interest, and some capital gains from foreign holdings. You, as a shareholder, may qualify for a deduction or offsetting credit under U.S. tax law for your portion of the Funds' foreign tax obligation provided you meet certain conditions as required by the Internal Revenue Service.

CONSOLIDATED FINANCIAL HIGHLIGHTS

The fiscal year end of each Fund is December 31. The audited consolidated financial highlights as of and for the twelve months ended December 31, 2019 of the Target Fund and the Survivor Fund are included with this Proxy Statement as Exhibit B.

The financial highlights of the Target Fund and the Survivor Fund are also contained in the Annual Report to shareholders of the Target Fund and Survivor Fund for the fiscal year ended December 31, 2019, which have been audited by Cohen & Company, Ltd., the Funds' registered independent public accounting firm. The Annual Report, which has previously been sent to shareholders, is available on request and without charge by writing to the Funds at One Beacon Street, Boston, MA 02108 and, with respect to the Target Fund and Survivor Fund, are incorporated by reference into this Proxy Statement.

INFORMATION RELATING TO THE PROXYREORGANIZATION

Description of the Reorganization

The following summary is qualified in its entirety by reference to the Plan found in Exhibit A.

The Plan provides that substantially all of the assets and liabilities of the Target Fund will be transferred to the Survivor Fund in exchange solely for shares of the Survivor Fund. The shares of the Survivor Fund issued to the Target Fund will have an aggregate net asset value equal to the aggregate net asset value of the Target Fund's shares outstanding as of the close of trading on the NYSE on April 3, 2020 (the "Closing Date") as determined in accordance with the Survivor Fund's valuation procedures. Upon receipt by the Target Fund of the shares of the Survivor Fund, the Target Fund will distribute Survivor Fund shares to its shareholders and will be terminated as a series of the Trust.

The distribution of the Survivor Fund shares to the Target Fund shareholders will be accomplished by opening new accounts on the books of the Survivor Fund in the names of the Target Fund shareholders and transferring to those shareholder accounts the shares of the Survivor Fund. For shares held through financial intermediaries and broker dealers, accounts will be opened on the books of the Survivor Fund at the financial intermediary or broker dealer. Shareholders are not expected to receive new accounts as a result of the Reorganization. Such newly-opened accounts on the books of the Survivor Fund will be established on the transfer agent's record and represent the respective pro rata number of shares of the Survivor Fund that the Target Fund is to receive under the terms of the Plan. See "Terms of the Reorganization" below.

Accordingly, as a result of the Reorganization, each Target Fund shareholder will own shares of the Survivor Fund with an aggregate net asset value equal to the aggregate net asset value of the shares of the Target Fund that the shareholders owned immediately prior to the Reorganization.

No sales charge or fee of any kind will be assessed to the Target Fund shareholders in connection with their receipt of shares of the Survivor Fund in the Reorganization.

The Plan contains customary representations, warranties, and conditions. The Plan may be terminated with respect to the Reorganization if, on the Closing Date, any of the required conditions have not been met or if the representations and warranties are not true. The Plan may be terminated or amended by the mutual consent of the parties.

Reasons for the Reorganization

The Board considered that the Target Fund and Survivor Fund have identical investment goals and investment strategies, and similar fundamental and non-fundamental investment limitations. The Board observed that the Target Fund and Survivor Fund had comparable performance for the past three to five years, and noted that the Survivor Fund had a longer track record. The Board considered that merging the Target Fund into the Survivor Fund would improve the Survivor Fund's prospects for attracting assets, which would achieve certain operating efficiencies and economies of scale as a result of the larger net asset size. The Board discussed that more assets in the Survivor Fund would increase the likelihood of its stability, long-term viability and liquidity. They noted that the cost of the proposed merger would be paid by the Adviser, and that the merger was not expected to result in a taxable event for shareholders. After further discussion, the Board concluded that the merger of the Target Fund into the Survivor Fund was in the best interests of each Fund, as well as each Fund's respective shareholders, and that the Target Fund's shareholders would not have their interests diluted as a result of the merger. The approval determinations were made on the basis of each Trustee's business judgment after consideration of all of the factors taken as a whole, though individual Trustees may have placed different weight on various factors and assigned different degrees of materiality to various conclusions.

Federal Income Taxes

The combination of the Target Fund and the Survivor Fund in the Reorganization is expected to qualify for federal income tax purposes as a separate tax-free reorganization under Section 368(a) of the Internal Revenue Code of 1986, as amended (the "Code"). As a condition of the closing of the Reorganization and consistent with market practice, the Trust will receive, on April 3, 2020 a legal opinion from Thompson Hine LLP to the effect that the Reorganization should be a tax-free reorganization. Accordingly, neither the Target Fund nor its shareholders should recognize gain or loss as a result of the Reorganization. The tax basis of the Survivor Fund shares received should be the same as the basis of the Target Fund shares exchanged and the holding period of the Survivor Fund shares received should include the holding period of the Target Fund shares exchanged, provided that the shares exchanged were held as capital assets at the time of the Reorganization. No tax ruling from the Internal Revenue Service regarding the Reorganization has been requested. Nevertheless, the sale of securities by the Target Fund prior to the Reorganization, whether in the ordinary course of business or in anticipation of the Reorganization, could result in taxable capital gains distribution prior to the Closing Date of the Reorganization. As of the date of this Proxy Statement, the Adviser does not intend to sell any securities held by the Target Fund in anticipation of the Reorganization but may do so in the ordinary course of business before the Reorganization. Prior to the Closing Date of the Reorganization, the Target Fund will pay to its shareholders a cash distribution consisting of any undistributed investment company taxable income and/or any undistributed realized net capital gains, including any net gains realized from any sales of assets prior to the Closing Date. This distribution would be taxable to shareholders that are subject to tax. Shareholders should consult their own tax advisers concerning the potential tax consequences of the Reorganization to them, including foreign, state and local tax consequences.

Expenses of the Reorganization

The costs of the Reorganization will be borne by the Adviser. The costs associated with the Reorganization are expected to be approximately $40,000-$50,000, not including the brokerage costs, if any, associated with the re-positioning of the Target Fund.

Continuation of Shareholder Accounts and Plans; Share Certificates

Upon consummation of the Reorganization, the Survivor Fund will establish an account on the transfer agent's record for each Target Fund shareholder on the books of the Survivor Fund containing the appropriate number of shares of the Survivor Fund to be received in the Reorganization. For shares held through financial intermediaries and broker dealers, accounts will be opened on the books of the Survivor Fund at the financial intermediary or broker dealer. Shareholders are not expected to receive new accounts as a result of the Reorganization. No certificates for shares of the Survivor Fund will be issued in connection with the Reorganization.

OTHER INFORMATION

Capitalization

The following table sets forth, as of December 31, 2019. (a) the unaudited capitalization of each Fund and (b) the unaudited combined capitalization of the Survivor Fund assuming the Reorganization has taken place. The capitalizations are likely to be different on the Closing Date as a result of daily Fund share purchase, redemption and market activity. No assurance can be given as to how many shares of the Survivor Fund will be received by Target Fund shareholders at the Closing Date, and the information should not be relied upon to reflect the number of shares of the Survivor Fund that actually will be received by Target Fund shareholders.

The Proxy

The Board is soliciting proxies so that each shareholder has the opportunity tocan vote on the proposals to be considered at the Meeting.meeting. A proxy card for voting your shares at the Meeting is enclosed. The shares represented by each valid proxy received in time will be voted at the Meetingmeeting as specified. If no specification is made, the shares represented by a duly executed proxy will be voted for Proposals 1 and 2,approval of each proposal described in this Proxy Statement and at the discretion of the holders of the proxy on any other matter that may come properly before the Meeting about which the Trust did not have notice of a reasonable time prior to the mailing of this Proxy Statement.meeting. You may revoke your proxy at any time before it is exercised by (i)(1) submitting a duly executed proxy bearing a later date, (ii)(2) submitting a written notice to the SecretaryPresident of the Trust revoking the proxy, or (iii)(3) attending and voting in person at the Meeting.

VOTING SECURITIES AND VOTINGShareholder Information

As of the Record Date, there were 6,258,244.472 shares outstanding of the followingTarget Fund. As of the Record Date, no person was known by the Target Fund to own beneficially or of record 5% or more of any class of shares of beneficial interestthe Target Fund except as follows:

As of the FundsRecord Date, there were issued17,043,183.056 shares outstanding of the Survivor Fund. As of the Record Date, no person was known by the Survivor Fund to own beneficially or of record 5% or more of the Survivor Fund except as follows:

A shareholder who owns of record or beneficially more than 25% of the outstanding shares of a Fund or who is otherwise deemed to "control" a Fund may be able to determine or significantly influence the outcome of matters submitted to a vote of the Fund's shareholders.

Security Ownership of Management

To the best knowledge of the Trust, there were no Trustees or officers of the Trust who were the owners of more than 1% of the outstanding shares of a Fund on the Record Date.

Voting Securities and outstanding:Voting

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