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Exhibit 10.10--Form of Working Capital Agreement by and between the Company 
               and Prime Retail, Inc.

                           WORKING CAPITAL AGREEMENT

     This Working Capital Agreement (the "Agreement") is entered into this 
15th day of June, 1998 by and between Prime Retail, Inc., a Maryland 
corporation ("Prime"), Prime Retail, L.P., a Delaware limited partnership 
("Prime L.P."), Horizon Group Properties, Inc., a Maryland corporation 
("HGP") and Horizon Group Properties, L.P., a Delaware limited partnership 
("HGP LP").

     WHEREAS, the transactions contemplated by that certain Amended and 
Restated Agreement of Merger dated as of February 1, 1998 (the "Merger 
Agreement") by and among Prime Retail, Inc., a Maryland corporation, Prime 
Retail, L.P., a Delaware limited partnership, Horizon Group, Inc. a Michigan 
corporation ("Horizon"), Sky Merger Corp., a Maryland corporation ("Sky 
Merger"), HGP, HGP LP and Horizon/Glen Outlet Centers Limited Partnership, a 
Delaware limited partnership ("Horizon Partnership"), will be consummated 
concurrently herewith;

     WHEREAS, the parties hereto wish to set forth their understanding with 
respect to various working capital and other matters in connection with the 
consummation of the transactions contemplated by the Merger Agreement and the 
Contribution Agreement (as defined in the Merger Agreement);

     NOW, THEREFORE, in consideration of good and valuable consideration, the 
receipt and sufficiency of which is hereby acknowledged, the parties hereto 
do hereby agree as follows:

     1.   WORKING CAPITAL FACILITY.  HGP LP has assumed from Horizon 
Partnership the obligations (the "Obligations") outstanding under or 
otherwise existing pursuant to or as set forth in that certain Business Loan 
Agreement dated as of August 1, 1996 (such agreement, as amended prior to the 
date hereof, and the documents executed in connection therewith, the "Loan 
Agreement") by and between Huntington National Bank and Horizon Partnership.  
The Loan Agreement matures on August 1, 1998.  HGP LP agrees to use its best 
efforts to refinance the Obligations as soon as possible following the 
Closing Date (as defined in the Merger Agreement); provided, however, any 
such refinancing shall be on terms and conditions reasonably acceptable to 
HGP LP.  In the event that such Obligations are not refinanced prior to the 
maturity date of the Loan Agreement, Prime and/or Prime LP agrees to enter 
into a two year term loan with HGP LP pursuant to which Prime and/or Prime LP 
will make available to HGP LP up to $4,000,000 in aggregate principal amount 
of indebtedness, upon terms and conditions substantially the same as those 
set forth in the Loan Agreement; provided that the interest rate shall be 10% 
per annum and the loan will be repayable prior to the maturity date thereof 
from the proceeds of (i) a sale of the outlet center in Algondones, New 
Mexico to the extent it is not used to repay another obligation on which 
Prime is contingently liable or (ii) a completion of an equity offering by 
HGP or HGP LP.

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     2.   (a) WORKING CAPITAL ADJUSTMENT. The parties hereto understand and 
agree that a definitive amount of Working Capital (as hereinafter defined) is 
to be transferred to HGP, HGP LP and the other Horizon Entities (as 
hereinafter defined) in connection with the transfer of the properties listed 
on APPENDIX A hereto (the "Contributed Properties") and pursuant to the terms 
of the Merger Agreement and the Contribution Agreement.  Such working capital 
is in consideration of, among other things, the assumption by the Horizon 
Entities, of the known and unknown liabilities of the Contributed Properties 
in connection with the Formation Transactions (as hereinafter defined).  The 
parties hereto agree that the amount of Working Capital to be transferred, in 
the aggregate, to the Horizon Entities is $545,000 and that such amount shall 
be calculated and adjusted as set forth herein.  On the date hereof, Prime 
shall transfer cash to HGP and fund the reserves set forth on the Settlement 
Sheet attached hereto. The cash funding occurring on the date hereof is 
seventy-five percent (75%) of the amount of cash anticipated to be required 
to be made to HGP to comply with the working capital adjustment set forth 
herein.
     
          (b)  PREPARATION OF FINAL STATEMENTS.  As promptly as practicable 
after the date hereof and in any event not later than forty-five (45) days 
hereafter, HGP shall prepare and deliver to Prime an unaudited statement of 
assets and liabilities of each of the Contributed Properties as of the date 
hereof (the "Final Statements").  The delivery of the Final Statements shall 
not create any presumption as to the accuracy or completion  thereof.  The 
Final Statements shall be prepared in a manner consistent with Section 2(e) 
hereof and in accordance with GAAP.  Prime and its representatives and 
auditors shall be afforded the opportunity to review all underlying financial 
records and work papers pertaining to the preparation of the Final Statements 
and HGP shall permit Prime and its representatives full access to the books 
and records in HGP's possession relating to the Contributed Properties to 
permit Prime to review the Final Statements.  The aggregate Current Assets 
and Current Liabilities of the Contributed Properties as shown on the Final 
Statements prepared by HGP shall be final and binding for purposes of this 
Agreement unless Prime shall give written notice to HGP of disagreement with 
the values thereon involving more than $25,000 in the aggregate within thirty 
(30) business days following its receipt of the Final Statements, specifying 
in reasonable detail the nature and extent of such disagreement.  If Prime 
objects to the Final Statements and the parties are unable to resolve such 
dispute within fifteen (15) days after HGP's receipt of such notice, the 
dispute shall be submitted for determination to Ernst & Young.  Such public 
accounting firm shall review and decide the issues that are the subject of 
such dispute as specified in such notice as soon as possible after such 
submission and in any event within fifteen (15) days.  The decision of such 
accounting firm shall be set forth in writing and delivered to Prime and HGP. 
The decision of such accounting firm shall be final and binding Prime and 
HGP.  The fees and costs of such public accounting firm shall be borne 
equally by Prime and HGP.
     
          (c)  PAYMENTS.  If the aggregate amount of Working Capital of the 
Contributed Properties, as reflected on the Final Statements, shall exceed 
$545,000, then the excess shall be paid in cash by HGP to Prime.  If the 
aggregate amount of Working Capital of the Contributed Properties, as 
reflected on the Final Statements, shall be less than $545,000, then the 
shortfall shall be paid in cash by Prime to HGP.

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          (d)  FEES AND EXPENSES.  Prime and HGP shall each pay their own 
costs incurred in preparing and/or reviewing the Final Statements, including 
the fees and expenses of their auditors.

          (e)  DEFINITION OF CURRENT ASSETS AND CURRENT LIABILITIES.  
APPENDIX B sets forth a hypothetical balance sheet of a Contributed Property 
setting forth, for illustrative purposes only, the line items and categories 
of assets and liabilities which shall be deemed to constitute "Current 
Assets" and "Current Liabilities."  For purposes of this Agreement, Current 
Assets and Current Liabilities shall refer to items and categories of assets 
and liabilities so identified on said APPENDIX B, together with other items 
of a similar nature which may be reflected on the Final Statements and shall 
include without limitation, as a type of current assets, the escrows being 
funded by Prime on the date hereof and shall include as a type of current 
liability, real estate taxes and accrued capital items such as tenant 
improvement allowances and leasing commission for transactions entered into 
prior to the date hereof.  For the purposes hereof, (i) "Working Capital" 
shall mean Current Assets Less Current Liabilities and (ii) "HGP Entities" 
shall mean, collectively, HGP, HGP LP and the respective corporations, 
limited liability companies and limited partnerships owned directly or 
indirectly by HGP after giving effect to the consummation of all of the 
transactions contemplated by the Merger Agreement (the "Formation 
Transactions"). The parties agree that the matters set forth in Schedule 2.8 
of the disclosure letter attached to the Merger Agreement and prepared by 
Horizon Group, Inc. (other than that disclosed in numbered paragraph ten 
thereof) shall be the obligations of Prime.

          The parties agree that the benefits and obligations set forth in 
the in the Guarantee and Indemnity Agreement among the parties hereto dated 
the date hereof and the underlying indebtedness owed to third parties 
referenced therein shall not be included as Current Assets or Current 
Liabilities.

     3.   CONTROL.  The parties understand and agree that to the extent of 
any inconsistencies between this Agreement and the Merger Agreement or this 
Agreement and the Contribution Agreement, the terms and provisions of this 
Agreement shall control.

     4.   MODIFICATION OR AMENDMENT.  The parties hereto may modify or amend 
this Agreement by written agreement executed and delivered by authorized 
officers of the respective parties.

     5.   COUNTERPARTS.  For the convenience of the parties hereto, this 
Agreement may be executed in separate counterparts, each such counterpart 
being deemed to be an original instrument, and which counterparts shall 
together constitute the same agreement.

     6.   GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED 
IN ACCORDANCE WITH, THE LAWS OF THE STATE OF MARYLAND, REGARDLESS OF THE LAWS 
THAT MIGHT OTHERWISE GOVERN UNDER APPLICABLE PRINCIPLES OF CONFLICT OF LAWS 
THEREOF.

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     7.   NOTICES.  Any notice, request, instruction or other document to be 
given hereunder by any party to the other shall be in writing and shall be 
deemed to have been duly given (i) on the date of delivery if delivered by 
facsimile (upon confirmation of receipt) or personally, (ii) on the first 
business day following the date of dispatch if delivered by Federal Express 
or other reputable next-day courier service or (iii) on the third business 
day following the date of mailing if delivered by registered or certified 
mail, return receipt requested, postage prepaid.  All notices hereunder shall 
be delivered as set forth below, or pursuant to such other instructions as 
may be designated in writing by the party to receive such notice.

                    If to HGP or HGP LP:

                    Horizon Group Properties, Inc.
                    5000 Hakes Drive
                    Norton Shores, MI 49441
                    Attention:     Gary J. Skoien
                    Fax: No.:      (616) 798-5100

                    with a copy to:

                    Winston & Strawn
                    35 West Wacker Drive
                    Chicago, IL 60601
                    Attention:     Wayne D. Boberg, Esq.
                    Fax No.:       (312) 558-5700

                    If to Prime or Prime LP:

                    Prime Retail, Inc.
                    100 East Pratt Street
                    19th Floor
                    Baltimore, Maryland 21202
                    Attention:     Michael W. Reschke
                                   Robert P. Mulreaney
                                   C. Alan Schroeder
                    Fax No.:       (410) 234-1703

                    With a copy to:

                    Winston & Strawn
                    35 W. Wacker Drive
                    Chicago, Illinois 60601
                    Attention:     Steven J. Gavin
                    Fax No.:       (312) 558-5700

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     8.   ASSIGNMENT.  Nothing contained in this Agreement or the agreements 
referred to herein (except as otherwise expressly set forth therein) is 
intended to confer on any person or entity other than the parties hereto and 
their respective successors and permitted assigns any benefit, rights or 
remedies under or by reason of this Agreement and such other agreements.

     9.   JOINT AND SEVERAL LIABILITY.   The obligations of HGP and HGP LP on 
the one hand and Prime and Prime LP on the other hand shall be joint and 
several.

     10.  ENFORCEMENT.  The parties agree that irreparable damage would occur 
in the event that any of the provisions of this Agreement were not performed 
in accordance with their specific terms or were otherwise breached.  It is 
accordingly agreed that the parties shall be entitled to an injunction or 
injunctions to prevent breaches of this Agreement and to enforce specifically 
the terms and provisions of this Agreement in any federal court located in 
Maryland this being in addition to any other remedy to which they are 
entitled at law or in equity.  In addition, each of the parties hereto (a) 
consents to submit itself (without making such submission exclusive) to the 
personal jurisdiction of any federal court located in Maryland in the event 
any dispute arises out of this Agreement or any of the transactions 
contemplated by this Agreement and (b) agrees that it will not attempt to 
deny or defeat such personal jurisdiction by motion or other request for 
leave from any such court.

                              [signature page follows]

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

                                   HORIZON GROUP PROPERTIES, INC.

                                   By: /s/ Gary J. Skoien
                                      -------------------------------
                                   Its: President
                                       ------------------------------

                                   HORIZON GROUP PROPERTIES, L.P.

                                   By: Horizon Group Properties, Inc.

                                   Its: General Partner

                                   By: /s/ Gary J. Skoien
                                      -------------------------------
                                   Its: President
                                       ------------------------------

                                   PRIME RETAIL, INC.

                                   By: /s/ William H. Carpenter, Jr.
                                      -------------------------------
                                   Its: President
                                       ------------------------------
                                   PRIME RETAIL, L.P.

                                   By:  Prime Retail, Inc.

                                   Its:  General Partner

                                   By: /s/ William H. Carpenter, Jr.
                                      -------------------------------
                                   Its: President
                                       ------------------------------


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