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                                                                  EXHIBIT 10.3


                                 AMENDMENT NO. 1
                                       TO
                      AMENDED AND RESTATED CREDIT AGREEMENT

     AMENDMENT NO. 1 dated as of August 12, 1998 of the Amended and Restated
Credit Agreement dated as of April 29, 1998 (the "AMENDED AND RESTATED
AGREEMENT") among United Asset Management Corporation, a Delaware corporation
(the "BORROWER"), the banks listed on the signature pages thereof, Morgan
Guaranty Trust Company of New York, as Administrative Agent (the "ADMINISTRATIVE
AGENT"), and BankBoston, N.A., as Collateral Agent (the "COLLATERAL AGENT").

     WHEREAS, the Borrower proposes to issue (i) up to $67,000,000 in aggregate
principal amount of its 8.52% Senior Secured Notes, Series A, due July 25, 2005,
(ii) up to $75,000,000 in aggregate principal amount of its 8.52% Senior Secured
Notes, Series B, due July 25, 2008 and (iii) up to $108,000,000 in aggregate
principal amount of its 8.72% Senior Secured Notes, Series C, due July 25, 2008
(collectively, the "1998 SENIOR NOTES") pursuant to several Note Purchase
Agreements substantially in the form of Exhibit B to the Amendment and Consent
referred to below (as such Note Purchase Agreements may be amended, supplemented
or otherwise modified from time to time in accordance with the terms thereof,
the "1998 NOTE PURCHASE AGREEMENTS");

     WHEREAS, the obligations of the Borrower in respect of the 1998 Senior
Notes are to be guaranteed by each of the Guaranty Subsidiaries substantially in
the form of Exhibits C-1 through C-5 to the Amendment and Consent referred to
below (as the same may be amended, supplemented or otherwise modified from time
to time in accordance with the terms thereof, the "1998 SENIOR NOTE
GUARANTIES");

     WHEREAS, the obligations of the Borrower and the Guaranty Subsidiaries in
respect of the 1998 Senior Notes and the 1998 Senior Note Guaranties are to be
secured by the Collateral from time to time held by the Collateral Agent under
the Collateral Documents pursuant to the Amendment and Consent dated as of
August 12, 1998, in the form delivered to the Banks (the "AMENDMENT AND
CONSENT");

     WHEREAS, the relative rights and priorities of the Banks, the Agents and
the holders of the 1995 Senior Notes (as defined below) and of the 1998 Senior
Notes with respect to the Collateral and the guaranties made by the Guaranty


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Subsidiaries in favor of the Agents and the Banks and the holders of the 1995
Senior Notes and the 1998 Senior Notes, respectively, are to be governed by a
Collateral Agency and Intercreditor Agreement, as amended by the First Amendment
thereto (the "INTERCREDITOR AMENDMENT"); and

     WHEREAS, the parties hereto desire to enter into this Amendment in order to
(i) permit the Borrower to enter into the 1998 Note Purchase Agreements and to
issue the 1998 Senior Notes pursuant thereto and to perform its obligations
thereunder, (ii) permit the Guaranty Subsidiaries to enter into the Senior Note
Guaranties and to perform their respective obligations thereunder and (iii)
effect certain other amendments to the Amended and Restated Agreement;

     NOW, THEREFORE, the parties hereto agree as follows:

     SECTION 1. Definitions.

     (a) Unless otherwise specifically defined herein, each term used herein
which is defined in the Amended and Restated Agreement shall have the meaning
assigned to such term in the Amended and Restated Agreement.

     (b) The following definitions are added to Section 1.01 of the Amended and
Restated Agreement in the appropriate alphabetical order:

          "1995 SENIOR NOTES" means the Borrower's $150,000,000 7.12% Senior
     Secured Notes due August 25, 2005.

          "1998 SENIOR NOTES" means the Borrower's $67,000,000 8.52% Senior
     Secured Notes, Series A, due July 25, 2005, $75,000,000 8.52% Senior
     Secured Notes, Series B, due July 25, 2008, and $108,000,000 8.72% Senior
     Secured Notes, Series C, due July 25, 2008.

     (c) The definition of "Senior Notes" in Section 1.01 of the Amended and
Restated Agreement is amended to read as follows:

     "SENIOR NOTES" means the 1995 Senior Notes and the 1998 Senior Notes.

     SECTION 2. Commitment Fee. Section 2.08(a) of the Amended and Restated
Agreement is amended to read as follows:

          (a) The Borrower shall pay to the Administrative Agent, for the
     account of the Banks ratably in proportion to their Commitments, a
     commitment fee calculated for each day at the Commitment Fee Rate for 


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     such day (determined in accordance with the Pricing Schedule) on the amount
     by which the aggregate amount of the Commitments exceeds the aggregate
     outstanding principal amount of the Loans on such day. Such commitment fee
     shall accrue from and including the Effective Date to but excluding the
     date on which the Commitments terminate in their entirety.

Each occurrence of the phrase "Facility Fee Rate" in the Amended and Restated
Agreement is replaced by the phrase "Commitment Fee Rate".

     SECTION 3. Limitation on Debt. Section 5.10 of the Amended and Restated
Agreement is amended as follows:

     (a) each occurrence of the words "Senior Notes" is replaced by the words
"1995 Senior Notes"; and

     (b) the following is added in the appropriate alphabetical order as
subsection (c-1):

          (c-1) Debt in an aggregate principal amount not to exceed $250,000,000
     incurred in respect of the 1998 Senior Notes, as the principal amount
     thereof may be reduced from time to time in accordance with the terms
     thereof;

     SECTION 4. Events of Default. Section 6.01(k) is amended by replacing the
number $900,000,000 with the number $1,150,000,000.

     SECTION 5. Consents. The undersigned Banks hereby consent to and instruct
the Collateral Agent to execute the Amendment and Consent and the Intercreditor
Amendment.

     SECTION 6. Counterparts; Effectiveness. This Amendment may be executed in
one or more counterparts, each of which, when so executed and delivered, shall
be deemed to be an original and all of which counterparts, taken together, shall
constitute but one and the same Amendment with the same force and effect as if
the signatures of all of the parties were on a single counterpart, and it shall
not be necessary in making proof of this Amendment to produce more than one such
counterpart. This Amendment shall become effective upon the latest to occur of:

     (a) receipt by the Administrative Agent of duly executed counterparts
hereof signed by the Borrower and the Banks (or, in the case of any party as to
which an executed counterpart shall not have been received, the Administrative


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Agent shall have received telegraphic, telex, facsimile or other written
confirmation from such party of execution of a counterpart hereof by such
party);

     (b) effectiveness of the Intercreditor Amendment in accordance with its
terms; and

     (c) effectiveness of the Amendment and Consent in accordance with its
terms..

     SECTION 7. Governing Law. This Amendment shall be governed by, and
construed and enforced in accordance with, the internal laws of the State of New
York (without reference to conflict of laws principles).

     IN WITNESS WHEREOF, this Amendment has been duly executed and delivered as
of the date first above written.


                                UNITED ASSET MANAGEMENT 
                                 CORPORATION


                                By__________________________
                                  Title:


                                BANKBOSTON, N.A., as Collateral 
                                 Agent and Bank


                                By___________________________
                                  Title:


                                MORGAN GUARANTY TRUST 
                                 COMPANY OF NEW YORK


                                By___________________________
                                  Title:


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                                DEUTSCHE BANK AG NEW YORK 
                                 AND/OR CAYMAN ISLANDS 
                                 BRANCHES


                                By___________________________
                                  Title:


                                By___________________________
                                  Title:


                                BANK OF AMERICA NT & SA


                                By___________________________
                                  Title:


                                THE CHASE MANHATTAN BANK


                                By___________________________
                                  Title:


                                MELLON BANK, N.A.


                                By___________________________
                                  Title:


                                NATIONSBANK, N.A.


                                By___________________________
                                  Title:


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                                CITIBANK, N.A.


                                By___________________________
                                  Title:


                                COMMERZBANK AG NEW YORK 
                                 BRANCH


                                By___________________________
                                  Title:


                                By___________________________
                                  Title:


                                CREDIT LYONNAIS NEW YORK 
                                 BRANCH


                                By___________________________
                                  Title:


                                THE FIRST NATIONAL BANK OF 
                                 CHICAGO


                                By___________________________
                                  Title:


                                FLEET NATIONAL BANK


                                By___________________________
                                  Title:


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                                THE ROYAL BANK OF SCOTLAND 
                                 PLC


                                By___________________________
                                  Title:


                                BANQUE PARIBAS


                                By___________________________
                                  Title:


                                By___________________________
                                  Title:


                                BAYERISCHE VEREINSBANK AG


                                By___________________________
                                  Title:


                                By___________________________
                                  Title:


                                THE LONG-TERM CREDIT BANK OF 
                                 JAPAN, LIMITED, NEW YORK 
                                 BRANCH


                                By___________________________
                                  Title:


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                       STATE STREET BANK AND TRUST 
                        COMPANY


                       By___________________________
                         Title:


                       THE BANK OF NEW YORK


                       By___________________________
                         Title:


                       SOCIETE GENERALE, NEW YORK BRANCH


                       By___________________________
                         Title:


                       UNION BANK OF CALIFORNIA, N.A.


                       By___________________________
                         Title:



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