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                                                                    Exhibit 10



                         UNITED ASSET MANAGEMENT CORPORATION
                              DEFERRED COMPENSATION PLAN
                                           
                                   FIRST AMENDMENT


    WHEREAS, United Asset Management Corporation (hereinafter referred to as
the "Company") adopted the United Asset Management Corporation Deferred
Compensation Plan (hereinafter referred to as the "Plan") effective as of
January 1, 1994 to provide retirement benefits for certain employees of the
Company; and

    WHEREAS, in accordance with Section 10 of the Plan, the Company wishes to
amend the Plan;

    NOW, THEREFORE, the Plan is hereby amended effective as of July 1, 1997, as
follows:

1.  In Subsection 8.5 of Section 8, Subparagraph (i) of Paragraph (b) is
amended to read and provide as follows:

(b) Notional Shares Election.

    (i)  The Election.  Each Participant may elect to have all or any portion
of his or her Allocations under the Plan (including all or any portion of his or
her existing Account that was previously invested under the Mutual Fund
Election) be deemed to be invested in Notional Shares.  All such elections shall
be made on a form prescribed by the Retirement Committee and shall be subject to
the following requirements and restrictions:

    (1)  The election with respect to any Allocations made for a Plan Year
shall be received by the Retirement Committee on or before the second-to-last
day of such Plan Year (or on such earlier business day as the Retirement
Committee may set for any Plan Year if such second-to-last day is not a business
day) for a deemed investment in Notional Shares as of the last business day on
or after the last day of such Plan Year; 

    (2)  The election with respect to any portion of an existing Account
previously invested (or deemed to be invested) under the Mutual Fund Election
shall be effective on the next business day after it is received by the
Retirement Committee; 



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    (3)  No investment or reinvestment in Notional Shares will be made to the
extent that the Retirement Committee determines that such action would likely
result in more Notional Shares being credited to Accounts under the Plan than
could be paid out as shares of Stock pursuant to paragraph (b) of Subsection
7.2; 

    (4)  To the extent that a Notional Shares Election cannot be carried out
because of clause (3) above or because it is received by the Retirement
Committee after the deadline in clause (1) above, it will be deemed to be a
Mutual Fund Election and the mutual fund or funds chosen for investment of the
Allocation or Account shall be as selected by the Retirement Committee until
such time as the Participant gives effective investment instructions pursuant to
Paragraph (a) of this Subsection 8.5 or clause (2) of this Paragraph (b), as
applicable; and 

    (5)  Once made, investment of an Allocation or reinvestment of any portion
of an existing Account in Notional Shares is irrevocable.

2.  In Subsection 8.5 of Section 8, Subparagraph (ii) of Paragraph (b) is
amended to read and provide as follows:

    (ii) The Investment.  As of the date that any deemed investment in Notional
Shares takes place, the number of Notional Shares credited to the Participant's
Account shall be determined by dividing the amount of the Allocation to be
invested and/or the value of the Account to be reinvested by the closing price
of the Stock on its principal trading exchange as of such date (or on the last
previous day on which a trade occurred if no trade of the Stock occurred on the
relevant date), with any resulting fractional Notional Share rounded up to the
next whole Share.

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    Except as specifically amended hereby, the Plan is hereby reaffirmed in all
respects.

    Signed as a sealed Massachusetts instrument effective as of the date stated
above.

                             UNITED ASSET MANAGEMENT CORPORATION
                             
                             
                             
                             By: /s/ William H. Park  
                                 -----------------------------------------
                                 William H. Park, Executive Vice President
                             
July 22, 1997
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Date