UNITED ASSET MANAGEMENT CORPORATION
                         PROFIT SHARING AND 401(k) PLAN

                                 FIFTH AMENDMENT


     WHEREAS, United Asset Management Corporation (hereinafter referred to as
the "Company") adopted the United Asset Management Corporation Profit Sharing
and 401(k) Plan (hereinafter referred to as the "Plan") effective as of January
1, 1989 and restated effective January 1, 1990, to provide retirement benefits
for certain employees of the Company and its subsidiaries; and

     WHEREAS, in accordance with Article 11, the Company wishes to amend the
Plan;

     NOW, THEREFORE, the Plan is hereby amended effective as of January 1, 2000,
unless otherwise indicated, as follows:

1.   Section 1.18 is amended to read and provide as follows:

     "Employee" means any person employed by the Company or an Affiliated
     Company, excluding, however, (i) any such person who is a member of a unit
     of Employees covered by a collective bargaining agreement, unless such
     agreement provides for the application of the Plan to the Employees in such
     unit; (ii) any such person who is a non-resident alien; (iii) any such
     person who executes a waiver of participation in the Plan or an agreement
     not be classified as an Employee (provided that any such waiver or
     agreement shall conform to the requirements of Treasury Regulations Section
     1.401(k)-1(a)(3)(iv), as amended, or any applicable successor rules); and
     (iv) any person who is determined or agrees not to be a common-law employee
     of the Company or any Affiliated Company or who is classified as a
     non-employee by the Company or Affiliated Company using such person's
     services, regardless of whether such determination or classification was
     erroneous and regardless of the person's actual employment status. (Such
     determination, agreement or classification shall be in writing but may be
     in any form elected by the Company or an Affiliated Company, such as,
     without limitation, an employment record, memorandum or letter.) Without
     limiting the generality of the foregoing, the term Employee shall exclude
     all persons who are classified as independent contractors, consultants,
     contract workers or the like. If a person is not an Employee because of an
     erroneous determination or classification as to the person's employment
     status, or if a person's agreed-upon status changes, or if a person who was
     classified as a non-Employee is reclassified as an Employee, such person
     shall not be entitled to participate in the Plan retroactively or to
     receive any retroactive benefits or other compensation on account of any
     period prior to the date of the reclassification, corrected determination,
     or change in agreed-upon status, but each such person shall be credited
     with Hours of
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     Service under the Plan for all service as a common-law employee of the
     Company or any Affiliated Company to the extent required by applicable law.

     Notwithstanding anything to the contrary in this Plan, any person who is a
     leased employee (as defined in Section 414(n)(2) of the Code, without
     regard to Section 414(n)(5) of the Code) of the Company or an Affiliated
     Company shall be treated as an Employee under this Plan solely for the
     purpose of crediting such person with Hours of Service towards eligibility
     and vesting under the Plan if and when such person ceases to be a leased
     employee and becomes an Employee within the meaning of the definition above
     in this section. Such persons shall also be counted to the extent required
     by Section 410(b) of the Code in determining whether the Plan meets the
     coverage requirements imposed by such section, but such persons shall not
     otherwise be eligible for participation in this Plan except as specifically
     provided for in the Plan.

2.   Section 1.40 is amended to read and provide as follows:

     "Valuation Date" means the last day of each calendar month or any other
     date as determined by the Committee. In the event that the Committee
     authorizes daily valuation, the Valuation Date shall be the close of
     business on each day that the New York Stock Exchange is open and
     conducting business.

3.   The first sentence of the first paragraph of Section 3.1 is amended to read
     and provide as follows:

     Each Participant may elect to have contributions made to the Plan on the
     Participant's behalf as provided below.

4.   The second and fourth sentences of the first paragraph of Section 3.1 are
     deleted in their entirety.

5.   The second paragraph of Section 3.1 is amended to read and provide as
     follows:

     Contributions made pursuant to this Section 3.1 shall be remitted to the
     Trustee or a custodian appointed by the Committee as soon as is
     administratively practicable but in any event within any time limit that
     may be prescribed from time to time by applicable regulations.

6.   Section 3.1(a) is amended to read and provide as follows:

     Before-Tax Contributions - Subject to any uniform limit as may be set from
     time to time by the Committee and in whatever manner as may be prescribed
     from time to time by the Committee, a Participant may elect to have the
     Company contribute an amount of such Participant's Compensation under a
     Salary Deferral Agreement.

7.   The first sentence of the first paragraph of Section 3.2 is amended to read
     and provide as follows:

     A Participant may elect to change the Participant's rate of After-Tax
     Contributions under the Participant's payroll deduction authorization as of
     the first day of any payroll period,


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     provided that the Participant (i) executes a new payroll deduction
     authorization at least thirty (30) days in advance or (ii) if authorized by
     the Committee, communicates such election by telephone or electronic means
     directly to the Company at least thirty (30) days in advance and executes a
     new payroll deduction authorization before the first day of the payroll
     period during which the election becomes effective.

8.   The first sentence of the second paragraph of Section 3.2 is amended to
     read and provide as follows:

     A Participant may elect to change the Participant's rate of Before-Tax
     Contributions under the Participant's Salary Deferral Agreement as of the
     first day of any payroll period, provided that the Participant (i) executes
     a new Salary Deferral Agreement at least thirty (30) days in advance or
     (ii) if authorized by the Committee, communicates such election by
     telephone or electronic means directly to the Company at least thirty (30)
     days in advance and executes a new Salary Deferral Agreement before the
     first day of the payroll period during which the election becomes
     effective.

9.   Section 3.4 is amended by adding a new Section 3.4(f) as follows:

     Notwithstanding anything to the contrary, a note may not be transferred to
     the Trust Fund pursuant to this Section 3.4.

10.  The third paragraph of Section 4.1 is amended to read and provide as
     follows:

     The Company Contribution (if any) made by any Company on account of a Plan
     Year shall be (a) allocated among each Participant who (i) is eligible
     during such Plan Year under the provisions of Section 2.2, (ii) is an
     active Employee on the last day of such Plan Year; and (iii) received any
     portion of his or her Compensation for such Plan Year from such Company and
     (b) allocated in the proportion that the amount of each Participant's
     Compensation paid for such Plan Year by such Company bears to the total
     Compensation paid to all eligible Participants for such Plan Year by such
     Company, subject to the limitations specified in this Article IV.

11.  The first sentence of Section 5.3 is amended to read and provide as
     follows:

     The Participant may, as of any Valuation Date subsequent to such
     Participant's initial participation in the Plan and upon notice at least
     thirty (30) days prior to such Valuation Date, elect to have such
     Participant's future contributions invested in a proportion different from
     that previously selected. Notice pursuant to this Section 5.3 shall be in
     writing or, if authorized by the Committee, through communication by
     telephone or electronic means directly from the Participant to the Company.

12.  The first sentence of Section 5.7 is amended to read and provide as
     follows:

     Upon notice to the Committee in writing or, if authorized by the Committee,
     through communication by telephone or electronic means directly from the
     Participant to the Committee, each Participant may elect that any portion
     of the Participant's interest (in increments of 1%) in any fund (except the
     Loan Fund) be transferred to any other fund


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     (except the Loan Fund). Such election shall become effective as soon as is
     administratively practicable.

13.  The first sentence of the second paragraph of Section 5.8(a) is amended to
     read and provide as follows:

     Valuations of such accounts shall be made at such times as the Committee
     may require, but no less frequently than monthly.

14.  The first sentence of Section 6.4 is amended to read and provide as
     follows:

     In the event a Participant is reemployed prior to incurring five
     consecutive Breaks in Service, any non-vested amount of such Participant's
     Company Account which was forfeited shall be restored to such Participant's
     Company Account on the Valuation Date coincident with or next succeeding
     the later of the Participant's reemployment date or the date that the
     Participant repays the full amount of any prior distribution, not including
     any interest thereon, to the Plan.

15.  Section 7.3(a) is amended to read and provide as follows:

     (a)  in installments as soon as practicable after the last day of each
          calendar month, commencing with the calendar month that includes the
          applicable Valuation Date determined under Section 7.2, over a period
          of not more than fifteen (15) years, the amounts of which are
          calculated by dividing (i) the then current value of the Participant's
          Total Account as of the final Valuation Date in each month for which
          an installment is due by (ii) the remaining number of unpaid
          installments, including the installment then being calculated; or

16.  The last paragraph of Section 7.3(b) is deleted in its entirety.

17.  Section 7.5(i) is amended to read and provide as follows:

     No benefit account of $5,000 or less shall be eligible for deferral of a
     lump-sum payment or for installment payments.

18.  Section 7.8(b) is amended to read and provide as follows:

     in the event the Participant's vested interest in the Trust Fund is $5,000
     or less, his vested interest shall be distributed in a lump sum
     distribution as soon as practicable after the first Valuation Date that
     follows his date of termination by at least ten (10) days in the amount
     determined as of such Valuation Date.

19.  The first sentence of Section 7.8(c) is amended to read and provide as
     follows:

     in the event the Participant's vested interest in the Trust Fund exceeds
     $5,000, a lump sum distribution of such vested interest shall be deferred
     unless the Participant elects distribution at an earlier date.


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20.  The first sentence of the last paragraph of Section 8.1 is amended to read
     and provide as follows:

     The withdrawal shall be made as soon as is administratively practicable but
     in any event no later than thirty (30) days after the date on which the
     request for the withdrawal is received.

21.  The third paragraph of Section 8.5 is amended to read and provide as
     follows:

     The loan shall be made as soon as is administratively practicable but in
     any event no later than thirty (30) days after the date on which is the
     loan application is received.

22.  Section 8.6(e) is amended to read and provide as follows:

     Repayment shall be made by payroll deduction of substantially equal amounts
     in each of the borrower's payroll periods, commencing no later than 3
     months following the date that the loan or any portion of the loan is
     disbursed; provided that a borrower who commences an unpaid leave of
     absence shall continue making repayments by check on such schedule as the
     Committee shall approve (such approval to be made in a uniform and
     non-discriminatory manner); provided further that such payments by check
     shall be scheduled in substantially equal installments not less frequently
     than quarterly. Each loan shall be scheduled for repayment over a period of
     not more than (i) 5 years from the date that the loan or any portion of the
     loan is disbursed; or (ii) 30 years from the date the loan or any portion
     of the loan is disbursed if such loan is used to acquire any dwelling unit
     which within a reasonable period of time is to be used (determined at the
     time the loan is made) as the principal residence of the Participant.

23.  Section 8.6(f) is deleted in its entirety.

24.  Section 8.6(l) is deleted in its entirety.

25.  Sections 8.6(g), (h), (i), (j), (k), (m), (n) and (o) are redesignated
     Sections 8.6(f), (g), (h), (i), (j), (k), (l), and (m), respectively.

26.  Redesignated Section 8.6(f) is further amended to read and provide as
     follows:

     Full or partial repayment of the outstanding balance may be made by check
     as of any Valuation Date after the Valuation Date on which the loan was
     made.

27.  Redesignated Section 8.6(g) is further amended to read and provide as
     follows:

     The amount of each repayment, including principal and interest, shall be
     credited to each fund in accordance with the Participant's then current
     investment election.

28.  Article 9 is amended by adding the following new Section 9.9:

     9.9  Obligation to Pay Expenses


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          Expenses incurred in administering the Plan, including those necessary
          for the administration of the Trust Fund, shall be paid out of the
          principal or income of the Trust Fund unless paid by the Company.
          Notwithstanding the foregoing, the Company shall not have any
          obligation to pay any of such expenses.

29.  Section 12.3 is amended by adding the following new third paragraph:

     A domestic relations order will not fail to be deemed a qualified domestic
     relations order merely because it requires the distribution or segregation
     of all or part of a Participant's Total Account with respect to an
     alternate payee prior to the Participant's earliest retirement age (as
     defined in Section 414(p) of the Code) under the Plan. A distribution to an
     alternate payee prior to the Participant's attainment of the earliest
     retirement age is available only if (a) the order specifies distribution at
     that time and (b) if the present value of the alternate payee's benefits
     under the Plan exceeds $5,000, the alternate payee consents to such
     distribution.

     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

December 7, 1999                                 /s/  William H. Park
----------------------------------------         -------------------------------
(Date)                                           William H. Park
                                                  Executive Vice President and
                                                   Chief Financial Officer


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