Exhibit 10.66

AMENDMENT
TO
EXCHANGE RIGHTS AGREEMENT
(CLASS B OPERATING PARTNERSHIP UNITS)

          Amendment, dated as of December 17, 2003 (this “Amendment”), to
Exchange Rights Agreement dated as of January 2, 1998, among Starwood Hotels &
Resorts Worldwide, Inc. (the “Corporation”), SLC Operating Limited Partnership
(the “Operating Partnership”) and certain limited partners of the Operating
Partnership (the “Agreement”). All capitalized terms used in this First
Amendment and not otherwise defined herein shall have the respective meanings
assigned thereto in the Agreement.

          WHEREAS, the Board of Directors of the Corporation has determined that
it is advisable and in the best interests of the Corporation and its
shareholders to exercise the Corporation’s right pursuant to Section 2(c) of the
Agreement to modify the right to exchange Class B OP Units pursuant to the
Agreement, and the amendment thereto, dated October 10, 2002, as set forth in
this Amendment to extend the period of time during which the holders of Class B
OP Units can exchange such units for Class B EPS.

          NOW, THEREFORE, the Corporation agrees, for its benefit and the
benefit of the holders of Class B OP Units, as follows:

  1.   Notwithstanding anything contained in Section 2(a) of the Agreement or in
the form of Letter of Transmittal attached thereto as Exhibit A to the contrary,
a holder of Class B OP Units may make a Class B EPS Request in a Letter of
Transmittal delivered to the Trust after the Cross-Over Date and on or prior to
January 2, 2005.     2.   Except as otherwise specifically set forth herein, all
terms and provisions of the Agreement shall remain in full force and effect and
shall be unmodified by the effectiveness of this Amendment.

          IN WITNESS WHEREOF, Starwood Hotels & Resorts Worldwide, Inc. has
adopted this Amendment as of the date first above written.

                  STARWOOD HOTELS & RESORTS WORLDWIDE, INC.
 
           

  By:                

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      Name:   Kenneth S. Siegel

      Title:   Executive Vice President,
General Counsel and Secretary