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                                                                   EXHIBIT 99.10

                              DEVELOPMENT AGREEMENT
                          (Farmington Hills, Michigan)

         This DEVELOPMENT AGREEMENT (the "Agreement") is made as of this 1st day
of December, 1998, by and between SUNRISE DEVELOPMENT, INC., a Virginia
corporation ("Developer") KARRINGTON HEALTH, INC. ("Owner").

         WHEREAS, Owner desires to own and develop an assisted living project
(the "Facility") to be located in Farmington Hills, Michigan, as more
particularly described on Exhibit A (the "Site");

         WHEREAS, Owner, in anticipation of its pending merger with Sunrise
Assisted Living, Inc., the parent of Developer, has determined it is in Owner's
best interest to engage Developer in the development of Owner's projects
currently under construction in order to ensure an orderly transition upon the
consummation of the merger; and

         WHEREAS, Owner wishes to engage Developer for certain development and
construction services with respect to the Facility and Developer desires to
provide such services, pursuant to the terms set forth herein.

         NOW, THEREFORE, the parties hereto agree as follows:

                                    ARTICLE I
                        APPOINTMENT OF DEVELOPER AND TERM

         1.01 Appointment of Developer. Owner hereby appoints Developer and
Developer hereby accepts appointment, subject to the terms and conditions of
this Agreement, as development agent to provide certain development, design and
construction management services with respect to the Facility.

         1.02 Term. This Agreement shall begin upon execution by the parties and
continue until the date that the Facility is issued a certificate of occupancy
(the "Term").

                                   ARTICLE II
                         DUTIES AND RIGHTS OF DEVELOPER

         2.01 Project Budget Services. Developer shall provide budgeting
services as set forth in this Section 2.01. Developer shall prepare a pro forma
budget for the development and construction of the Facility, setting forth all
project costs, including all development, marketing, management, guaranty fees
and other costs to be paid to Developer and any affiliates thereof. The pro
forma budget shall also include a line item 


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for working capital/operating loss reserves. The pro forma shall be presented to
Owner for Owner's review and approval, and once approved by Owner (with any
revisions thereto accepted in writing by Developer), such pro forma shall
constitute the "Development Budget" for all purposes hereof. The Development
Budget shall be subject to the review and approval of the construction lender
for the Facility. If the construction lender requires any revisions to the
Development Budget, Owner and Developer shall cooperate in making such revisions
and shall mutually approve the modification required.

         2.02 Design and Construction Management Services. Developer shall
provide the following construction management services to Owner:

              a.   Assist Owner in coordinating with third-party architects and
                   engineers all necessary architectural services for the
                   Facility, including architectural, structural, mechanical,
                   electrical and plumbing/fire protection engineering services.

              b.   Coordinate preparation of all design development documents,
                   including all architectural, structural, electrical,
                   mechanical and plumbing plans and specifications necessary
                   for the construction of the Facility.

              c.   Prepare all construction bid documents, secure bids from the
                   general contractor, and assist Owner in negotiating the terms
                   of the construction contract. After Owner has approved the
                   terms of the construction contract, Developer shall have the
                   authority to execute the construction contract as agent for
                   Owner.

              d.   Develop and review critical path schedules and updates and
                   assist the general contractor in developing the project
                   schedule and updates.

              e.   Discuss and review with the general contractor its means and
                   methods of construction.

              f.   Discuss and review with the general contractor permitting
                   approval and licensing issues and requirements necessary to
                   complete and open the Facility, and obtain (or cause the
                   general contractor to obtain) all required permits.

              g.   Assist Owner as requested with construction management and
                   cost control services, including assisting Owner in obtaining
                   the most favorable prices for construction, equipment,
                   finishes and furnishings, and making recommendations to Owner
                   when 

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                   requested regarding change orders, extensions of time and
                   increases or decreases in the contract sum.

              h.   Assist Owner as requested in monitoring and evaluating
                   construction progress and make recommendations to the general
                   contractor and Owner as deemed necessary.

              i.   Assist in the resolution of critical issues impacting the
                   progress of work, and monitor architectural supplemental
                   instructions and requirements for information.

              j.   Provide quality control and the early detection of defects in
                   workmanship.

              k.   Review punch list items and assist in the close-out of the
                   project.

              l.   Coordinate opening date for the Facility with Owner and the
                   Facility's managing agent (the "Manager").

         2.03 Expenses. It is expressly understood that it is Owner's
responsibility to provide any and all funds needed for Developer to perform the
Development, Design and Construction Management Services, as set forth in the
Development Budget. Owner shall also be solely responsible for payment to all
third-parties (i.e. engineers, attorneys and consultants) as set forth in the
Development Budget.

         2.04 Reimbursement. Owner shall reimburse Developer for any and all
costs incurred by Developer in connection with the Site prior hereto. Developer
shall attach as Exhibit B hereto a list of such costs incurred to date. Owner
and Developer agree to reconcile such reimbursement of costs thirty (30) days
after the initial reimbursement, and any additional amounts determined to be
owing shall be promptly forwarded to the Developer.

                                   ARTICLE III
                            DEVELOPER'S COMPENSATION

         3.01 Development Fee. For the Design and Construction Management
Services provided pursuant to this Agreement, Developer shall be paid a fee
equal to a total amount of Two Hundred Fifty Thousand Dollars ($250,000.00) (the
"Development Fee"). Fifty Thousand Dollars ($50,00.00) of the Development Fee
shall be due to Developer as of the date of this Agreement for payment of
services performed by Developer at and prior to the date of this Agreement.
Owner acknowledges that Developer has assisted Owner since Owner and Sunrise
Assisted Living, Inc. entered into a Merger Agreement dated October 11, 1998. A
schedule for the periodic payment of the remaining $200,000.00 of the
Development Fee shall be agreed to by Owner and Manager 

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subsequent to the date of this Agreement, with the final payment of the
Development Fee to be due no later than the issuance of a Certificate of
Occupancy for the Facility.

         The Development Fee shall constitute full and complete payment to the
Developer, for all guarantees and services furnished or performed by the
Developer, in connection with this Agreement at any time prior to or following
the execution of this Agreement.

                                   ARTICLE IV
                                   TERMINATION

         4.01 Termination Upon Opening. This Agreement shall terminate upon the
opening of the Facility, unless sooner terminated pursuant to the provisions of
this Agreement provided that Owner's obligation to pay the Development Fee shall
survive such termination.

         4.02 Termination for Default. In the event that either the Owner or the
Developer is in default under any material term or condition of this Agreement
and fails either to cure or comply with such term or condition or to diligently
pursue such cure within forty-five (45) days after the service of written notice
of default, then the other of them may, at the expiration of such 45-day period
or such longer period as may be reasonably necessary to cure such default,
cancel and terminate this Agreement upon five (5) days' written notice. Upon any
such termination by Developer due to Owner's default (which may include Owner's
failure to proceed with the acquisition of title to the Site), the unpaid
balance of the Development Fee shall be fully due and payable.

         4.03 Bankruptcy of Either Party. If either Owner or Developer shall
cease to exist, for any reason, during the term of this Agreement, or in the
event a petition in bankruptcy, arrangement or reorganization is filed by or
against either of them and such petition is not dismissed within sixty (60)
days, or if either or them shall make an assignment for the benefit of creditors
or take advantage of any insolvency law, the other of them may forthwith
terminate this Agreement.

         4.04 Suspension of Performance. If development of the Facility
contemplated under this Agreement is suspended for any reason described in
Section 5.04 below, including without limitation any cause beyond the reasonable
control of the parties hereto, then upon written notice by the Owner to the
Developer (the "Notice of Suspension"), the Owner may suspend the Developer's
performance of its obligations under this Agreement for a period of ninety (90)
days. The Owner may terminate such suspension and re-commence development of the
project by written notice to the Developer whereupon the Developer shall
re-commence performing its obligations under this Agreement within thirty (30)
days of receipt of such notice.

         4.05 Failure to Obtain Financing. If the closing of the financing has
not occurred by April 1, 1999, then either party may terminate this Agreement
upon ten (10)

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days written notice to the other party. In the event of such termination, except
for material default by Developer, Owner will immediately pay to Developer any
outstanding Development Fee and shall immediately reimburse Developer for its
direct out-of-pocket expenses on the project.

                                    ARTICLE V
                            MISCELLANEOUS PROVISIONS

         5.01 Standard of Performance. Developer will devote its best efforts to
the development of the Facility as contemplated by this Agreement and will act
in good faith to cause the completion of the Facility in accordance with the
terms and conditions of this Agreement.

         5.02 Proprietary Information. Any and all architectural, structural,
engineering or other construction drawings furnished to Owner with regard to the
Facilities are the property of Developer. Owner shall not use any such drawings
or cause to have any such drawings disseminated to any third party without the
written consent of Developer. Without prejudice to any rights and remedies
otherwise available to Developer, Developer shall be entitled to equitable
relief by way of injunction if Owner breaches this Section 5.02. No failure or
delay by Developer in exercising any right, power or privilege hereunder shall
operate as a waiver thereof, nor shall any single or partial exercise thereof
preclude any other or further exercise thereof or the exercise of any other
right, power or privilege hereunder. Owner agrees to indemnify Developer for any
costs and expenses, including legal expenses, Developer may incur in connection
with the enforcement of this Section 5.02.

         5.03 Consent. Any consent, approval or other action required or
requested under or in connection with this Agreement shall not unreasonably be
withheld or delayed and any request made or direction given hereunder or in
connection herewith shall be reasonable, it being the intention and expectation
of the Owner and the Developer that neither shall be capricious or arbitrary
under or in connection with this Agreement. Any determination of reasonableness
under this Section shall be made in light of the objectives of the Owner, which
objectives include, without limitation, the development of the Facility as a
first class building and the operation of the Facility as a high quality
assisted living community.

         5.04 Force Majeure. With respect to any services to be furnished or
obligations to be performed hereunder, no party shall ever be liable for failure
to furnish or perform the same when prevented from doing so by Acts of God,
contractor delays, strike, lockout or labor unrest, explosion, sabotage,
breakdown, accident, order or regulation of or by any governmental authority, or
failure of supply, or inability despite the exercise of reasonable diligence to
obtain supplies, parts or employees or others necessary to furnish such
services, or because of war, riot, civil commotion or other emergency, or for
any cause beyond its reasonable control; provided, however, that the lack of
financial resources shall never be excused.

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         5.05 Assignment and Subcontract. Except as specifically provided in
this Agreement, neither Owner nor Developer may assign any of its rights or
delegate any of the obligations specified in this Agreement without the prior
written consent of the other party. Developer may not subcontract any of its
obligations under this Agreement, except to its affiliates, without the prior
written consent of Owner. Notwithstanding any such subcontracting permitted or
approved hereunder, Developer will remain primarily liable for the performance
of its obligations under this Agreement.

         5.06 Benefits of Agreement. This Agreement shall be binding upon and
inure to the benefit of the parties and their respective successors, assigns,
legal representatives and heirs, but nothing contained in this Section shall be
deemed to constitute a consent to any assignment otherwise restricted by this
Agreement.

         5.07 Indemnification.

         a.   Owner and Developer each agree that the other shall be and is
         indemnified, exonerated, and held harmless of, from and against any
         claim, loss, cost, damage, expense or other liability arising out of
         performance under this Agreement, excepting only liability attributable
         to negligence, willful misconduct or willful, wanton or reckless
         failure by a party, its agents, servants, employees or independent
         contractors to perform its or their respective obligations under this
         Agreement.

         b.   A person entitled to indemnification under this Section shall give
         notice to the indemnitor of the claim or other circumstances giving
         rise to a request for indemnification, promptly after becoming aware of
         same. If the indemnitor does not notify the person to be indemnified
         that it has assumed the defense of such claim within a fifteen (15) day
         period after receipt of the notice of the request for indemnification,
         then the person entitled to indemnification may assume the defense of
         such claim on behalf and at the expense of the indemnitor. Any
         compromise or settlement of any such claim shall be made only with the
         prior consent of the indemnitor, provided that such consent shall not
         be delayed or unreasonably withheld. If the indemnitor notifies the
         person to be indemnified that it has assumed the defense of such claim,
         the indemnitor may compromise or settle any claim for which
         indemnification is available under this Section, and the party entitled
         to indemnification may participate in the defense of such claim with
         its own legal counsel at its own expense.

         c.   In no event shall either party hereunder be liable to the other 
         for consequential damages, lost profits or punitive damages on account
         of a default under this Agreement or otherwise.

         5.08 Modification. Except as otherwise provided herein, neither this
Agreement nor any provision hereof can be modified, changed, discharged,
extended or 

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terminated except by an instrument in writing executed by the party against whom
enforcement is sought.

         5.09 Waiver. The failure to insist upon strict compliance with any of
the terms, covenants or conditions herein on one or more occasions shall not be
deemed a waiver of such terms, covenants or conditions nor shall such failure
impose any obligation to provide notice that strict compliance will be expected
in the future, nor shall nay waiver or relinquishment of any right at any one or
more times be deemed a waiver or relinquishment of such right at any other time
or times.

         5.10 Notices. All notices, demands, consents, approvals, and requests
given by either party to the other hereunder shall be in writing and shall be
sent by hand, by overnight courier, or by registered or certified mail, return
receipt requested, postage prepaid, to the parties at the following addresses:

         Owner:           Karrington Health, Inc.
                          919 Old Henderson  Rd.
                          Columbus, Ohio  43220
                          Attn: Pete A. Klisares, President

         Copy to:         Stephen Lewis, Esquire
                          Karrington Health, Inc.
                          919 Old Henderson  Rd.
                          Columbus, Ohio  43220

         Developer:       Sunrise Development, Inc.
                          9401 Lee Highway, Suite 300
                          Fairfax, Virginia  22031
                          Attn: Thomas B. Newell, President

or to such other address and to the attention of such other person as either
party may from time to time designate in writing. Notices shall be effective
upon receipt. Refusal to accept delivery shall constitute receipt.

         5.11   Severability. If any term or provision of this Agreement or the
application thereof to any person or circumstance is held to be invalid or
unenforceable for any reason, the remainder of this Agreement, or the
application of such term or provision to persons or circumstances other than
those as to which it is held invalid or unenforceable, shall not be affected
thereby, and each term and provision of this Agreement shall be valid and be
enforced to the fullest extent permitted by law, but only to the extent the same
continues to reflect fairly the intent and understanding of the parties
expressed by this Agreement taken as a whole.

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         5.12   Governing Law. To the maximum extent the parties hereto may
lawfully agree, this Agreement shall be governed by, and construed in accordance
with, the laws of the Commonwealth of Virginia without regard to conflict of
laws principles, and shall be enforced in the state and federal courts located
in the Commonwealth of Virginia. Each of the parties to this Agreement submits
to the jurisdiction of the courts of that state and agrees that process may be
served upon it by registered or certified mail addressed as provided in Section
5.10.

         5.13   Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed to be an original, but all of which
taken together shall constitute one and the same document.

         5.14   Mediation. The parties agree that any disputes arising hereunder
shall be submitted to non-binding mediation in accordance with the rules of the
American Arbitration Association prior to the commencement of litigation by
either party. Any applicable statute of limitation or repose shall be tolled
from the date of filing of the request for mediation with the American
Arbitration Association until ten (10) days after the mediation is concluded.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed under seal by their duly authorized officers, all as of the day and
year first above written.

WITNESS/ATTEST:             OWNER:

                            Karrington Health, Inc., an Ohio corporation

/s/ Amy S. Maxwell          By:  /s/ Pete A. Klisares
------------------             ----------------------
                            Name: Pete A. Klisares
                                 -----------------    
                            Title:President
                                  --------- 


                            DEVELOPER:

                            Sunrise Development, Inc., a Virginia corporation

/s/ Susan L. Timoner        By:  /s/ Thomas B. Newell
--------------------           ----------------------
                                 Thomas B. Newell, President


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                                    Exhibit A

Situated in the State of Michigan, in the County of Oakland and in the City of
Farmington Hills:

Part of the Southeast 1/4 of Section 2 Town 1 North, Range 9 East described as:
Commencing at the East 1/4 corner of Section 2, Town 1 North, Range 9 East, City
of Farmington Hills, Oakland County, Michigan; thence South 01 degrees 30
minutes 02 seconds West 1671.81 feet along the East line of said Section and the
centerline of Middlebelt Road; thence North 87 degrees 40 minutes 18 seconds
West 60.01 feet to a point on the Westerly right-of-way of Middlebelt Road, said
point being the Point of Beginning; thence South 01 degrees 30 minutes 02
seconds West 314.23 feet along said right-of-way line; thence North 87 degrees
36 minutes 36 seconds West 452.24 feet; thence North 01 degrees 30 minutes 02
seconds East 472.02 feet; thence South 87 degrees 40 minutes 18 seconds East
254.40 feet; thence South 02 degrees 16 minutes 52 seconds West 158.26 feet;
thence South 87 degrees 40 minutes 18 seconds East 199.99 feet to the point of
beginning.

SIDWELL NO.  23-02-476-010 AND SIDWELL NO.  23-02-476-007

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