Exhibit 10.172

                                    AGREEMENT

      THIS AGREEMENT (this "Agreement") made as of this 10th day of August, 1999
by and between CAREMATRIX OF MASSACHUSETTS, INC., a Delaware corporation ("CMI")
and CHANCELLOR OF MERRILVILLE, INC., a Delaware corporation ("Chancellor").

                               W I T N E S S E T H

      WHEREAS, Chancellor is the lessee and operator of a certain senior housing
facility (the "Facility") located in Merrilville, Indiana, pursuant to that
certain lease agreement dated as of November 13, 1997 (the "Chancellor Facility
Lease"); and

      WHEREAS, pursuant to the terms of the Chancellor Facility Lease, CMI is a
permitted assignee of Chancellor's interest in the Chancellor Facility Lease;
and

      WHEREAS, CMI and Chancellor are parties to a certain Management Agreement
dated as of September 26, 1997 with respect to the Facility (as the same may
have been amended to date, the "Management Agreement"), pursuant to which CMI
provides certain management services to Chancellor with respect to the Facility;
and

      WHEREAS, pursuant to the terms of the Management Agreement, CMI (or its
affiliate) has the option to lease the Facility (the "Lease Option");

      NOW, THEREFORE, in consideration of the premises and the mutual covenants
herein contained, the parties hereto hereby agree as follows:

      1.    Concurrent with the execution and delivery of this Agreement, and in
            connection with CMI's Lease Option, CMI has paid to Chancellor the
            sum of $700,000, as a lease commitment fee (the "Lease Commitment
            Fee"), representing payment in full of any and all amounts due from
            CMI to Chancellor with respect to the Lease Option.

      2.    Chancellor hereby acknowledges receipt of the Lease Commitment Fee,
            and agrees that the Lease Commitment Fee represents payment in full
            of any and all amounts due from CMI to Chancellor with respect to
            the Lease Option.

      3.    In consideration of the payment of the Lease Commitment Fee, (a) the
            lease entered into pursuant to the Lease Option shall (at CMI's
            option, but subject to any requirements of the lessor under the
            Chancellor Facility Lease and its lender) either be (i) an
            assignment by Chancellor of its rights and obligations under the
            Chancellor Facility Lease, or (ii) a sublease of the Chancellor
            Facility Lease, such sublease to be on substantially the same terms
            and conditions as the Chancellor Facility Lease, and

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            (b) Chancellor shall not agree to any amendment to modification of
            the Chancellor Facility Lease without the prior approval of CMI.

      4.    Chancellor hereby acknowledges that CMI is in possession of the
            Facility.

      5.    Chancellor and CMI each hereby covenant and agree to take such
            further actions as the other deems reasonably necessary to enable
            the parties to receive the respective benefits contemplated by this
            Agreement.

      6.    This Agreement (i) shall be binding upon and inure to the benefit of
            the parties hereto and their respective successors and assigns, (ii)
            shall be governed by the laws of the Commonwealth of Massachusetts,
            and (iii) may not be modified orally, but only by a writing signed
            by each of CMI and Chancellor.

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      IN WITNESS WHEREOF, the parties hereto have duly executed this Agreement
as of the date and year first above written.


                                    CHANCELLOR OF MERRILVILLE, INC.


                                    By: /s/ Abraham D. Gosman
                                        ----------------------------------------
                                        Name:
                                        Title:
                                        hereunto duly authorized


                                    CAREMATRIX OF MASSACHUSETTS, INC.


                                    By: /s/ David B. Currie
                                        ----------------------------------------
                                        Name: David B. Currie
                                        Title: Senior Vice President
                                        hereunto duly authorized