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                                                                    EXHIBIT 10.6

                                                              A25-Westin Chicago

                    ASSIGNMENT AND ASSUMPTION OF AGREEMENTS

     This ASSIGNMENT AND ASSUMPTION OF AGREEMENTS ("Assignment"), is made as of 
the 31st day of December, 1997 ("Effective Date"), by and between WESTIN HOTEL 
COMPANY, a Delaware corporation, as assignor ("Assignor"), and 909 NORTH 
MICHIGAN AVENUE CORPORATION, a Delaware corporation, as assignee ("Assignee").

                              W I T N E S S E T H
                              - - - - - - - - - -

     WHEREAS, Assignor heretofore entered into, or is the current holder of 
certain interests by assignment, by operation of law, or otherwise under, each 
of the agreements, documents and instruments set forth on EXHIBIT A attached 
hereto and, by this reference, made a part hereof (all of such agreements, 
documents and instruments, as the same may have been amended, restated, 
exchanged, substituted, extended or otherwise modified from time to time 
(together with any miscellaneous papers, documents, letter agreements or other 
instruments anywise relating or incidental thereto or to the management or 
operation of the hotel referred to herein) hereinafter sometimes are referred to
collectively as, the "Assigned Agreements"), in connection with that certain 
hotel and related facilities commonly known as the Westin Chicago Hotel;

     WHEREAS, Assignor desires to sell, assign, transfer and convey unto 
Assignee all of Assignor's right, title, and interest in, to, and under the 
Assigned Agreements; and

     WHEREAS, subject to, and in accordance with, the terms, provisions and 
conditions of this Assignment, Assignee has agreed to accept such assignment and
transfer, and assume all of Assignor's right, title and interest, in, to, and 
under the Assigned Agreements;

     NOW, THEREFORE, in consideration of the mutual covenants and obligations 
set forth herein and for other good and valuable consideration, the receipt and 
sufficiency of which are hereby acknowledged, the parties hereto hereby agree as
follows:

     1.   RECITALS.  The foregoing recitals shall constitute an integral part of
this Assignment, and this Assignment shall be construed in consideration 
thereof.

     2.   ASSIGNMENT.  As of the Effective Date, subject to the terms, 
provisions and conditions of this Assignment, Assignor hereby ASSIGNS, CONVEYS, 
TRANSFERS, AND 

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                                                              A25-Westin Chicago

DELIVERS unto Assignee, all of Assignor's right, title and interest in, to and 
under each and all of the Assigned Agreements.

     3.   ASSUMPTION. As of the Effective Date, subject to the terms, provisions
and conditions of this Assignment, (a) Assignee hereby accepts the assignment of
Assignor's right, title and interest in, to and under each and all of the
Assigned Agreements, and (b) Assignee hereby assumes all obligations and
liabilities of Assignor imposed under the terms of each and all of the Assigned
Agreements.

     4.  SUCCESSORS. This Assignment shall be binding upon, and shall inure to 
the benefit of, the parties hereto and their respective successors and assigns.

     5.  GOVERNING LAW. This Assignment shall be governed by, and construed in 
accordance with, the internal laws of the State of New York.

     6.  ENTIRE AGREEMENT. This Assignment embodies the complete agreement of 
the parties hereto with respect to the subject matter hereof, and cannot be 
altered, amended, or modified except by their written agreement.

     7.  COUNTERPARTS. This Assignment may be executed in two or more 
counterparts, each of which shall be deemed to be an original and all of which, 
when taken and construed together, shall constitute one and the same instrument.

     8.  HEADINGS.  Section headings contained herein are for the convenience 
of reference only, and shall not govern the interpretation of any of the 
provisions contained herein.

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                                                              A25-Westin Chicago

     IN WITNESS WHEREOF, the parties hereto have caused this Assignment to be 
executed as of the day and year first above written.

                                        ASSIGNOR:

                                        WESTIN HOTEL COMPANY,
                                        a Delaware corporation


                                        By:   /s/ Catherine L. Walker
                                              ----------------------------
                                        Name: Catherine L. Walker
                                              ----------------------------
                                        Its:  Sr. Vice President
                                              ----------------------------


                                        ASSIGNEE:

                                        909 NORTH MICHIGAN AVENUE
                                        CORPORATION, a Delaware corporation
                                       


                                        By:   /s/ Catherine L. Walker
                                              ----------------------------
                                        Name: Catherine L. Walker
                                              ----------------------------
                                        Its:  Vice President
                                              ----------------------------

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                                                              A25-Westin Chicago

                                   EXHIBIT A

                              ASSIGNED AGREEMENTS
                              -------------------

1.   Amended and Restated Management Agreement, dated as of August 21, 1986, by
     and among Assignor, Assignee, The Westin Chicago Limited Partnership and
     Westin Hotels Limited Partnership.