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                                                                   EXHIBIT 10.15

                                 LEASE GUARANTY

      This LEASE GUARANTY (this "Guaranty") is made and entered into to be
effective as of May 1, 2002 (the "Effective Date"), by BLC PROPERTIES I, LLC, a
Delaware limited liability company ("Guarantor"), in favor of CMCP-ROSWELL, LLC,
a Delaware limited liability company ("Landlord").

                                    RECITALS

      WHEREAS, as of the Effective Date, Landlord and BLC-ROSWELL, LLC, a
Delaware limited liability company, as "Tenant," have executed and entered into
that certain Lease Agreement (as the same may be renewed, extended, amended or
modified from time to time, the "Lease"), pertaining to that certain Leased
Property (as defined in the Lease Agreement);

      WHEREAS, Guarantor is an affiliate of Tenant, and Guarantor will derive
substantial direct and indirect benefit from the transactions contemplated by
the Lease; and

      WHEREAS, it is a condition to the entering into of the Lease by Landlord
that Guarantor shall have executed and delivered this Guaranty.

      NOW, THEREFORE, in consideration of the foregoing and for other good and
valuable consideration the receipt and sufficiency of which are hereby
acknowledged by Guarantor, and in order to induce Landlord to enter into the
Lease, Guarantor hereby agrees as follows:

      Section 1. GUARANTY. Guarantor hereby unconditionally and irrevocably
guarantees (i) the full and prompt payment of all rent and other sums required
to be paid by Tenant under the Lease, (ii) the full and timely performance of
all other terms, conditions, covenants and obligations of Tenant under the Lease
(as same may be amended, renewed, extended or modified), and (iii) any and all
expenses (including reasonable attorneys' fees and expenses) incurred by
Landlord in enforcing any rights under the Lease or this Guaranty (such
obligations, collectively, are referred to as the "Guaranteed Obligations").
Guarantor agrees that this Guaranty is a guarantee of payment and performance,
not collection, and that Guarantor is primarily liable and responsible for the
payment and performance of the Guaranteed Obligations. It is not necessary for
Landlord, in order to enforce payment and performance by Guarantor under this
Guaranty, first or contemporaneously to institute suit or exhaust remedies
against Tenant or others liable for any of the Guaranteed Obligations or to
enforce rights against any collateral securing any of it. With the exception of
the defense of prior payment, performance, or compliance by Tenant or Guarantor
of the Guaranteed Obligations which Guarantor is called upon to pay, or the
defense that Landlord's claim against Guarantor hereunder is barred by the
applicable statue of limitations, all defenses of the law of guaranty or
suretyship, including, without limitation, substantive defenses and procedural
defenses, are waived and released by Guarantor to the extent permitted by law.
Except as provided in the preceding sentence, under no circumstances will the
liability of Guarantor under this Guaranty be terminated either with respect to
any period of time when the liability of Tenant under the Lease continues, or
with respect to any circumstances as to which the Guaranteed Obligations have
not been fully discharged by payment or performance.

      Section 2. GUARANTY ABSOLUTE. Guarantor guarantees that the Guaranteed
Obligations will be paid and performed strictly in accordance with the terms of
the Lease. The liability and responsibilities of Guarantor under this Guaranty
shall be absolute and unconditional, shall not be subject to any counterclaim,
setoff, or deduction and shall not be released, discharged, affected or impaired
by (1) any change in the time, manner, or place of payment or performance of any
of the Guaranteed Obligations, or any other amendment or waiver of or any
consent to departure from or termination of the Lease, (2) any release or
discharge of Tenant in any bankruptcy, receivership or other similar
proceedings, (3) the impairment, limitation or modification of the liability of
Tenant or the estate

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of Tenant in bankruptcy or of any remedy for the enforcement of Tenant's
liability under the Lease, resulting from the operation of any present or future
provisions of any bankruptcy code or other statute or from the decision in any
court, the rejection or disaffirmance of the Lease in any such proceedings, or
the assignment or transfer of the Lease by Tenant, (4) any failure, omission or
delay on the part of Landlord, to enforce, assert or exercise any right, power
or remedy conferred on or available to Landlord in or by the Lease or this
Guaranty, or any action on the part of Landlord granting indulgence or extension
in any form whatsoever or any invalidity, irregularity or unenforceability as to
Tenant of all or any part of the Guaranteed Obligations or any security
therefore, (5) the waiver by Landlord of the performance or observance by Tenant
or Guarantor of any of the agreements, covenants, terms or conditions contained
in the Lease or this Guaranty, (6) any merger, consolidation, reorganization or
similar transaction involving Tenant even if Tenant is a disappearing party in
such transaction, (7) the inability of Landlord or any Tenant to enforce any
provision of the Lease for any reason, (8) any change in the corporate
relationship between Tenant and Guarantor or any termination of such
relationship, (9) any change in the ownership of all or any part of the member
interests of Tenant, (10) the inability of Tenant to perform, or the release of
Tenant or Guarantor from the performance of, any obligation, agreement,
covenant, term or condition under the Lease or this Guaranty by reason of any
law, regulation or decree, now or hereafter in effect, (11) any merger of the
leasehold estate of Tenant with the fee estate or any other estate in the Leased
Property, or (12) any disability or other defense of Tenant. Landlord and
Tenant, without notice to or consent by Guarantor, may at any time or times
enter into such modifications, extensions, amendments, or other covenants with
respect to the Lease as they may deem appropriate and Guarantor shall not be
released thereby, but shall continue to be fully liable for the payment and
performance of all liabilities, obligations and duties of Tenant under the Lease
as so modified, extended or amended.

      Section 3. REINSTATEMENT. Guarantor further agrees that, if at any time
all or any part of any payment theretofore applied to any of the Guaranteed
Obligations is or must be rescinded or returned for any reason whatsoever
(including, without limitation, the insolvency, bankruptcy or reorganization of
Guarantor), such Guaranteed Obligations shall, for the purposes of this
Guaranty, to the extent that such payment is or must be rescinded or returned,
be deemed to have continued in existence, notwithstanding such application, and
this Guaranty shall continue to be effective or be reinstated, as the case may
be, as to such Guaranteed Obligations, all as though such application had not
been made.

      Section 4. CERTAIN ACTIONS. Landlord may, from time to time at its
discretion and without notice to Guarantor, take any or all of the following
actions: (a) retain or obtain the primary or secondary obligation of any obligor
or obligors, in addition to Guarantor, with respect to any of the Guaranteed
Obligations; (b) extend or renew for one or more periods (regardless of whether
longer than the original period), or release or compromise any obligation of
Guarantor hereunder or any obligation of any nature of any other obligor
(including, without limitation, Tenant) with respect to any of the Guaranteed
Obligations; or (c) release or fail to perfect any lien upon or security
interest in, or impair, surrender, release or permit any substitution or
exchange for, all or any part of any property securing any of the Guaranteed
Obligations or any obligation hereunder, or extend or renew for one or more
periods (regardless of whether longer than the original period) or release or
compromise any obligations of any nature of any obligor with respect to any such
property.

      Section 5. WAIVER. To the extent permitted by applicable law, Guarantor
hereby expressly waives: (i) notice of the acceptance of this Guaranty, (ii)
except as otherwise provided in the Lease or the Guaranty notice of the
existence or creation or non-payment of all or any of the Guaranteed
Obligations, (iii) presentment, demand, notice of dishonor, protest and all
other notices whatsoever except as otherwise provided in the Lease or the
Guaranty, and (iv) all diligence in collection or protection of or realization
upon the Guaranteed Obligations or any thereof, any obligation hereunder, or any
security for or guaranty of any of the foregoing.

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      Section 6. WAIVER OF SUBROGATION. Guarantor hereby waives all rights of
subrogation which it may at any time otherwise have as a result of this Guaranty
to the claims of Landlord against Tenant and all contractual, statutory or
common law rights of reimbursement, contribution or indemnity from Tenant which
it may at any time otherwise have as a result of this Guaranty prior to final
payment and satisfaction of the Guaranteed Obligations.

      Section 7. MISCELLANEOUS.

      7.l Amendments, Etc. No amendment or waiver of any provision of this
Guaranty nor consent to any departure by Guarantor therefrom shall be effective
unless the same shall be in writing and signed by Landlord.

      7.2 Addresses for Notices. All notices hereunder shall be in writing,
personally delivered, delivered by overnight courier service, sent by facsimile
transmission (with confirmation of receipt), or sent by certified mail, return
receipt requested, addressed as follows, or to such other address as shall be
designated by Guarantor or Landlord in written notice to the other party:

      If to Tenant:              BLC-Roswell, LLC
                                 c/o Brookdale Living Communities, Inc.
                                 330 North Wabash Avenue
                                 Suite 1400
                                 Chicago, Illinois 60611
                                 Attention: R. Stanley Young
                                 Telephone: (312) 977-3720
                                 Facsimile: (312) 977-3699

      with a copy to:            Brookdale Living Communities, Inc.
                                 330 N. Wabash Avenue
                                 Suite 1400
                                 Chicago, Illinois 60611
                                 Attention:  General Counsel
                                 Telephone: (312) 977-3760
                                 Facsimile: (312) 977-3769

      and to:                    Douglas E. Wambach
                                 Burke, Warren, MacKay & Serritella, P.C.
                                 330 North Wabash Avenue, 22nd Floor
                                 Chicago, Illinois 60611
                                 Telephone: (312) 840-7019
                                 Facsimile: (312) 840-7900

      If to Guarantor:           BLC Properties I, LLC
                                 c/o Brookdale Living Communities, Inc.
                                 330 North Wabash Avenue
                                 Suite 1400
                                 Chicago, Illinois 60611
                                 Attention: R. Stanley Young
                                 Telephone: (312) 977-3720
                                 Facsimile: (312) 977-3699

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      with a copy to:            Brookdale Living Communities, Inc.
                                 330 N. Wabash Avenue
                                 Suite 1400
                                 Chicago, Illinois 60611
                                 Attention: General Counsel
                                 Telephone: (312) 977-3760
                                 Facsimile: (312) 977-3769

      and to:                    Douglas E. Wambach
                                 Burke, Warren, MacKay & Serritella, P.C.
                                 330 North Wabash Avenue, 22nd Floor
                                 Chicago, Illinois 60611
                                 Telephone: (312) 840-7019
                                 Facsimile: (312) 840-7900

      If to Landlord:            CMCP-Roswell, LLC
                                 c/o Capstead Mortgage Corporation
                                 8401 North Central Expressway, Suite 800
                                 Dallas, Texas 75225
                                 Attention: Andrew F. Jacobs
                                 Telephone: (214) 874-2350
                                 Facsimile: (214) 874-2398

      with a copy to:            Andrews & Kurth, L.L.P.
                                 1717 Main Street, Suite 3700
                                 Dallas, Texas 75201
                                 Attention: David Barbour
                                 Telephone: (214) 659-4400
                                 Facsimile: (214) 659-4401

      7.3 No Waiver; Remedies. No failure on the part of Landlord to exercise,
and no delay in exercising, any right hereunder shall operate as a waiver
thereof; nor shall any single or partial exercise of any right hereunder
preclude any other or further exercise thereof or the exercise of any other
right. The remedies herein provided are cumulative and not exclusive of any
other remedies available at law or equity.

      7.4 Continuing Guaranty; Transfer of Interest. This Guaranty shall create
a continuing guaranty and will (i) remain in full force and effect until payment
and performance in full and termination of the Guaranteed Obligations, (ii) be
binding upon Guarantor and its successors and assigns, and (iii) inure, together
with the rights and remedies of Landlord hereunder, to the benefit of Landlord
and its successors, as permitted under the Lease. Without limiting the
generality of the foregoing clause, if and when Landlord assigns or otherwise
transfers any interest held by it under the Lease to any other person, that
other person shall thereupon become vested with all the benefits held by
Landlord under this Guaranty.

      7.5 GOVERNING LAW. THIS GUARANTY SHALL BE GOVERNED BY, AND CONSTRUED AND
ENFORCED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF TEXAS.

      Section 8. INDUCEMENT TO LANDLORD. Guarantor acknowledges and agrees that
the execution and delivery of this Guaranty by Guarantor to Landlord has served
as a material inducement to Landlord to execute and deliver the Lease, and
Guarantor further acknowledges and agrees that but for

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the execution and delivery of this Guaranty by Guarantor, Landlord would not
have executed and delivered the Lease.

      Section 9. ATTORNEYS' FEES. Should it become necessary for Landlord to
execute any action or proceeding to enforce Guarantor's obligations under this
Guaranty due to the occurrence of default by Guarantor hereunder and Landlord
prevails in such action or proceeding, Landlord and in addition to the other
rights of Landlord hereunder, shall be permitted to recover from Guarantor the
reasonable attorney's fees, court costs related to the enforcement of the rights
of Landlord hereunder and any other related reasonable expenses incurred by
Landlord.

      Section 10. CUMULATIVE REMEDIES. The stated rights of Landlord under this
Guaranty shall be understood as not excluding any other legal or equitable
rights of Landlord against Guarantor not expressly set forth herein, but shall
be understood as being cumulative to all such all other legal and equitable
rights of Landlord arising out of Guarantor's obligations hereunder and not
expressly stated herein.

      Section 11. SUBMISSION TO JURISDICTION. Guarantor hereby irrevocably
submits to the non-exclusive jurisdiction of any State or Federal court located
in Dallas, Texas over any action, suit or proceeding to enforce or defend any
right under this Guaranty or otherwise arising from or relating to this
Guaranty, and Guarantor irrevocably agrees that all claims in respect of any
such action, suit or proceeding may be heard and determined in such court.
Guarantor hereby irrevocably waives, to the fullest extent that it may
effectively do so, the defense of an inconvenient forum or venue to the
maintenance of any such action, suit or proceeding. Guarantor hereby agrees that
a final, non-appealable judgment in any such action, suit or proceeding shall be
conclusive and may be enforced in other jurisdictions by suit on the judgment or
in any other manner provided by law.

      Section 12. WAIVER OF JURY TRIAL. Guarantor hereby waives, to the fullest
extent permitted by applicable law, any right to a trial by jury in any action,
suit or proceeding to enforce or defend any rights under this Guaranty or any
other transaction document or any amendment, instrument, document or agreement
delivered or which may in the future be delivered in connection herewith or
arising from or relating to any relationship existing in connection with this
guaranty, and agrees, to the fullest extent permitted by applicable law, that
any such action, suit or proceeding shall be tried before a court and not before
a jury.

      Section 13. COOPERATION, FURTHER ASSURANCES. Guarantor covenants, and
agrees to sign, execute and deliver or cause to be signed, executed and
delivered and to do or make, or to cause to be done or make, upon the written
request of Landlord, any and all agreements, instruments, papers, deeds, acts or
things, supplemental, confirming or otherwise, as may be reasonably required by
Landlord for the purpose of, or in connection with, the transaction contemplated
hereby. Upon full and final payment and performance of the Guaranteed
Obligations, Landlord agrees to execute a release for the benefit of Guarantor,
in form and content reasonably satisfactory to Landlord. Except to the extent
expressly provided otherwise in any guaranty or indemnity from Guarantor or its
Parent to Landlord or its Affiliates, in no event shall any trustee,
shareholder, member, guarantor, partner, employee, officer or beneficiary of
Guarantor be personally liable for any of the obligations of Guarantor
hereunder.

               [THE REMAINDER OF THIS PAGE IS INTENTIONALLY BLANK]

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      Guarantor has caused this Guaranty to be effective as of the Effective
Date.

                                         GUARANTOR:

                                         BLC PROPERTIES I, LLC,
                                         a Delaware limited liability company


                                         By:/s/ R. Stanley Young
                                             ___________________________________
                                         Name:  R. Stanley Young
                                         Title: Vice President