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                                                                   Exhibit 10.27

                                    AMENDMENT
                                     TO THE
                         AFFILIATED MANAGERS GROUP, INC.
                       LONG-TERM EXECUTIVE INCENTIVE PLAN


     This Amendment to the Affiliated Managers Group, Inc. Long-Term Executive
Incentive Plan (the "Plan") shall become effective upon approval by the
stockholders of a majority of the votes cast at a meeting of stockholders at
which a quorum is present or by written consent in accordance with applicable
law.

     1.   DEFINITION OF "CASH NET INCOME". Subparagraph (g) of Section 2 of the
Plan is hereby deleted in its entirety and the following substituted therefor:

     "`CASH NET INCOME' for any fiscal year shall mean the Company's earnings
     after interest expense and income taxes, but before depreciation, and
     amortization, deferred taxes and extraordinary items, as determined in
     accordance with generally accepted accounting principles for such fiscal
     year."

     2.   STATUS OF PLAN. Except as specifically amended hereby, the Plan shall
continue in full force and effect. From and after the date hereof, all
references in any agreements covering awards granted under the Plan shall be
deemed to be references to the Plan as hereby amended.


Amended as of April 12, 2002.