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                                                                    Exhibit 10.2

                               FIRST AMENDMENT TO
                     LIMITED LIABILITY COMPANY AGREEMENT OF
                           WESTFIELD PARTNERS, L.L.C.

         This FIRST AMENDMENT to the LIMITED LIABILITY COMPANY AGREEMENT of
WESTFIELD PARTNERS, L.L.C. (the "Company") is dated as of December 1, 1999,
among WESTFIELD CAPITAL MANAGEMENT COMPANY, INC., a Massachusetts corporation,
as the Manager, and the undersigned Members, comprising all of the Members of
the Company, effective as of the date hereof.

                                   WITNESSETH:

         WHEREAS, the Manager and the Members entered into a Limited Liability
Company Agreement dated as of July 7, 1999, (the "Agreement");

         WHEREAS, the Manager and the Members desire to revise the Agreement to
clarify the treatment of additional capital contributions to the Company by one
or more of the Manager and the Members;

         NOW THEREFORE, for good and valuable consideration the receipt and
sufficiency of which are hereby acknowledged, the parties hereby agree and the
Agreement is hereby amended as follows:

         1. DEFINITIONS. Terms used herein and not otherwise defined herein are
used herein as defined in the Agreement.

         2. CAPITAL CONTRIBUTIONS. Section 4.1 is hereby amended in its entirety
to read as follows:

         4.1 CAPITAL CONTRIBUTIONS. As of the date hereof, the Manager and the
         Members have made the initial Capital Contributions with respect to
         each Fund as set forth on Schedule I hereto. Neither the Manager nor
         any Member shall be required to make any additional Capital
         Contributions; provided, however, that the Manager shall amend Schedule
         I hereto to reflect any voluntary additional Capital Contributions as
         the Manager may accept in its sole discretion, and the Book Capital
         Account of the Manager or any Member making such voluntary additional
         Capital Contribution shall be adjusted accordingly pursuant to Section
         3.1 hereof.
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         3. INVESTMENT INCOME OR LOSS. Section 6.3 of the Agreement is hereby
amended by deleting the word "Initial" from the Section.

         4. Except as otherwise modified hereby, all other provisions of the
Agreement are hereby ratified, confirmed and approved and remain in full force
and effect.

         IN WITNESS WHEREOF, the undersigned, have executed this First Amendment
as of the date first written above.

                                 MANAGER

                                 Westfield Capital Management Company, Inc.

                                 By:  _____________________________________
                                      Name:  Stephen C. Demirjian
                                      Title:    Senior Vice President

                                 MEMBERS

                                 -------------------
                                 C. Michael Hazard

                                 -------------------
                                 Arthur J. Bauernfeind

                                 -------------------
                                 Stephen C. Demirjian

                                 -------------------
                                 William A. Muggia

                                 -------------------
                                 B. Randall Watts