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                                                                   EXHIBIT 10.12

                       PROTECTION OF BUSINESS AGREEMENT
                       --------------------------------


     THIS PROTECTION OF BUSINESS AGREEMENT (this "Agreement") is entered into as
of October 17, 1996, by and among Security Capital Atlantic Incorporated, a
Maryland corporation ("Atlantic"), Security Capital Pacific Trust, a Maryland
real estate investment trust ("PTR"), and Security Capital Group Incorporated, a
Maryland corporation ("SCG"), and Homestead Village Incorporated, a Maryland
corporation ("Homestead").

     WHEREAS, on the date hereof the parties are entering into a series of
related transactions as described in that certain Merger and Distribution
Agreement, dated as of May 21, 1996, among Atlantic, PTR, SCG and Homestead (the
"Merger Agreement"), pursuant to which, among other things, PTR, Atlantic and
SCG will cause their respective subsidiaries engaged in the conduct of the
extended-stay lodging business to be merged with and into Homestead;

     WHEREAS, Atlantic, PTR and SCG and their respective affiliates will
continue to engage in certain businesses after the date hereof;

     WHEREAS, as a condition to the consummation of the transactions
contemplated by the Merger Agreement, the parties hereto desire to enter into
certain agreements restricting the activities of Atlantic, PTR and SCG and their
respective affiliates; and

     WHEREAS, pursuant to the Merger Agreement, it is contemplated that
securities of Homestead will be distributed by PTR and Atlantic in a public
distribution to their respective shareholders.

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

     Section 1.  Definitions.  Capitalized terms used herein shall have the
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meanings set forth below:

     "Affiliate" with regard to any Person, means (a) any Person directly or
indirectly controlling, controlled by or under common control with such Person,
(b) any Person owning or controlling 10% or more of the outstanding voting
interests of such Person or (c) any Person of which such Person owns or controls
10% or more of the voting interests.  The term "Affiliates" and "Affiliated"
shall have correlative meanings.  For purposes of this Agreement, the term
"Affiliate" shall not include Security Capital U.S. Realty, a Luxembourg
corporation, or any Person controlled by Security Capital U.S. Realty and no
party hereto shall be deemed to be an Affiliate of any other party hereto.
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     "Extended-Stay Property" means real property that is or is planned to be
used primarily for lodging facilities generally offering studio apartments,
including cooking facilities, which are generally rented for incremental periods
of one week but shall not include any real property that is or is planned to be
used primarily as corporate apartments.

     "Interest" means any kind of right, title or interest (whether legal or
beneficial), whether such right, title or interest is held directly or
indirectly through an interest in a Person that either directly or indirectly
owns such interest, but excluding any interests in Homestead.

     "Multifamily Property" means real property that is or is planned to be used
primarily for garden style multifamily dwellings which are generally leased for
six-month to twelve-month periods and require security deposits and also
includes real property that is or is planned to be used primarily for master-
planned apartment neighborhoods.

     "Person" means an individual or any corporation, partnership, trust,
unincorporated association or any other legal entity; provided, however that,
for purposes of Sections 2, 3 and 4 hereof, the term "Person" shall not include
an individual.

     "Restricted Area" means the continental United States.

     Section 2.  Agreement not to Engage in Certain Activities.
                 --------------------------------------------- 

          (a)  During the term provided in Section 6 hereof, none of Atlantic,
     PTR or SCG nor any of their respective Affiliates shall, anywhere within
     the Restricted Area, directly or indirectly, engage in the ownership,
     operation, development, management or leasing of any Extended-Stay
     Property.

          (b)  During the term provided in Section 6 hereof, neither Homestead
     nor any of its Affiliates shall, anywhere within the Restricted Area,
     directly or indirectly, engage in the ownership, operation, development,
     management or leasing of any Multifamily Property.

     Section 3.  Atlantic, PTR and SCG Limitations on Protection of Business.
                 -----------------------------------------------------------  
Notwithstanding anything to the contrary contained in this Agreement, each of
Atlantic, PTR and SCG and their respective Affiliates may:

          (a)  be an owner of securities of any class of Homestead;

          (b)  be an owner of up to 5% of the outstanding shares of stock of any
     class of securities of a Person (public or private) primarily engaged in
     owning, operating, developing, managing or leasing Extended-Stay
     Properties, so long as Atlantic, PTR and SCG and their Affiliates have no
     active participation (except to the extent permitted by clauses (c) and (d)
     below) in the business of such Person;

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          (c)  be an owner of any amount of the outstanding shares of stock of
     any class of securities of a Person (public or private), a majority owned
     subsidiary, division, group, franchise or segment of which is engaged in
     owning, operating, developing, managing or leasing Extended-Stay
     Properties, so long as not more than 5% of such Person's consolidated
     revenues are derived from the ownership, operation, development, management
     or leasing of Extended-Stay Properties; and

          (d)  be an owner of the outstanding shares of stock of any class of
     securities of a Person (public or private) primarily engaged in a business
     other than owning, operating, developing, managing or leasing Extended-Stay
     Properties, including a Person primarily engaged in business as an owner,
     operator or developer of hotel properties, whether or not such Person owns,
     operates, develops, manages or leases any Extended-Stay Properties.

     Section 4.  Homestead Limitations on Protection of Business.
                 -----------------------------------------------  
Notwithstanding anything to the contrary contained in this Agreement, Homestead
and its Affiliates may:

          (a)  be an owner of securities of any class of any of Atlantic, PTR or
     SCG;

          (b)  be an owner of up to 5% of the outstanding shares of stock of any
     class of securities of a Person (public or private) primarily engaged in
     owning, operating, developing, managing or leasing Multifamily Properties,
     so long as Homestead and its Affiliates have no active participation
     (except to the extent permitted by clause (c) below) in the business of
     such Person; and

          (c)  be an owner of any amount of the outstanding shares of stock of
     any class of securities of a Person (public or private), a majority owned
     subsidiary, division, group, franchise or segment of which is engaged in
     owning, operating, developing, managing or leasing Multifamily Properties,
     so long as not more than 5% of such Person's consolidated revenues are
     derived from the ownership, operation, development, management or leasing
     of Multifamily Properties.

     Section 5.  Reasonable and Necessary Restrictions.  Each of the parties
                 -------------------------------------                      
hereto acknowledges that the restrictions, prohibitions and other provisions
hereof are reasonable, fair and equitable in scope, terms and duration, are
necessary to protect the legitimate business interests of each of the other
parties hereto, and are a material inducement to such party to enter into the
transactions contemplated by the Merger Agreement.

     Section 6.  Term.
                 ---- 

     6.1  General.  Subject to earlier termination pursuant to Section 6.2, this
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Agreement shall be effective from and after the date hereof and shall continue
in effect until the tenth anniversary of the date hereof.

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     6.2  Change in Control.  Notwithstanding anything to the contrary contained
          -----------------                                                     
herein, the provisions of Section 2 of this Agreement shall terminate and be of
no further force or effect upon the occurrence of a Change in Control.  As used
herein, "Change in Control" means the acquisition, directly or indirectly (other
than by purchase from PTR, Atlantic or SCG, or any of their respective
Affiliates), by any Person (or group of associated Persons acting in concert),
other than PTR, Atlantic, SCG, or their respective Affiliates, of 25% or more of
the outstanding shares of voting stock of Homestead, without the prior written
consent of the Board of Directors of Homestead.

     Section 7.  Specific Performance.  Each of the parties hereto acknowledges
                 --------------------                                          
that the obligations undertaken by it pursuant to this Agreement are unique and
that the other parties hereto will not have an adequate remedy at law if it
shall fail to perform any of its obligations hereunder, and each of the parties
hereto therefore confirms that the right of each other party hereto to specific
performance of the terms of this Agreement is essential to protect the rights
and interests of such party.  Accordingly, in addition to any other remedies
that any party hereto may have at law or in equity, each such party shall have
the right to have all obligations, covenants, agreements and other provisions of
this Agreement specifically performed by each other party, and each party shall
have the right to obtain preliminary and permanent injunctive relief to secure
specific performance and to prevent a breach or contemplated breach of this
Agreement by each other party hereto.

     Section 8.  Operations of Affiliated Parties.  Each of the parties hereto
                 --------------------------------                             
agrees that it will refrain from authorizing or permitting any Affiliated party
to perform any activities that would be prohibited by the terms of this
Agreement if such activities were performed by it.

     Section 9.  Ancillary Agreements.  Nothing contained in this Agreement
                 --------------------                                      
shall in any way restrict or impair the obligations and rights of any party
under the terms of any agreement entered into in connection with the
transactions contemplated by the Merger Agreement, including, without
limitation, the foreclosure by PTR or Atlantic under any mortgages secured by
the properties of Homestead and the operation of such properties subsequent to
such foreclosure.

     Section 10.  Miscellaneous Provisions.
                  ------------------------ 

     10.1  Interpretation.  The parties hereto acknowledge that the fundamental
           --------------                                                      
policies of this Agreement are to protect each other party's interest in its
respective business and to eliminate potential conflicts of interest that may
exist as a result of actions taken or proposed to be taken by the other parties
hereto, and this Agreement shall be construed and enforced in a manner
consistent with and in furtherance of these policies.

     10.2  Binding Effect.  Subject to any provisions hereof restricting
           --------------                                               
assignment, all covenants and agreements in this Agreement by or on behalf of
any of the parties hereto shall

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bind and inure to the benefit of their respective successors, assigns, heirs,
and personal representatives.

     10.3  Assignment.  None of the parties hereto may assign any of its rights
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under this Agreement, or attempt to have any other entity or individual assume
any of its obligations hereunder.

     10.4  Severability.  If performance of any provision of this Agreement, at
           ------------                                                        
the time such performance shall be due, shall transcend the limit of validity
prescribed by law, then the obligation to be performed shall be reduced to the
limit of such validity; and if any clause or provision contained in this
Agreement operates or would operate to invalidate this Agreement, in whole or in
part, then such clause or provision only shall be held ineffective, as though
not herein contained, and the remainder of this Agreement shall remain operative
and in full force and effect.  The parties shall negotiate in good faith a
replacement clause or provision as consistent with the ineffective clause or
provision as is practicable under law.

     10.5  Governing Law.  This Agreement, the rights and obligations of the
           -------------                                                    
parties hereto, and any claims or disputes relating thereto shall be governed by
and construed in accordance with the laws of the State of Maryland, not
including the choice-of-law rules thereof.

     10.6  Amendment.  Except as otherwise expressly provided in this Agreement,
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no amendment, modification or discharge of this Agreement shall be valid or
binding unless set forth in writing and duly executed by each of the parties
hereto.

     10.7  Waiver.  Any waiver by any party or consent by any party to any
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variation from any provision of this Agreement shall be valid only if in writing
and only in the specific instance in which it is given, and such waiver or
consent shall not be construed as a waiver of any other provision or as a
consent with respect to any similar instance or circumstance.

     10.8  Headings.  Section and subsection headings contained in this 
           --------      
Agreement are inserted for convenience of reference only, shall not be deemed to
be a part of this Agreement for any purpose, and shall not in any way define or
affect the meaning, construction or scope of any of the provisions hereof.

     10.9  No Presumption Against Drafter.  Each of the parties hereto have
           ------------------------------                                  
jointly participated in the negotiation and drafting of this Agreement.  In the
event of an ambiguity or a question of intent or interpretation arises, this
Agreement shall be construed as if drafted jointly by each of the parties hereto
and no presumptions or burdens of proof shall arise favoring any party by virtue
of the authorship of any of the provisions of this Agreement.

     10.10  Execution in Counterparts.  This Agreement may be executed in one
            -------------------------                                        
or more counterparts, none of which need contain the signatures of each of the
parties hereto and each of which shall be deemed an original.

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     10.11  Limitation of Liability.  Any obligation or liability whatsoever of
            -----------------------                                            
PTR which may arise at any time under this Agreement or any obligation or
liability which may be incurred by it pursuant to any other instrument,
transaction or undertaking contemplated hereby shall be satisfied, if at all,
out of PTR's assets only.  No such obligation or liability shall be personally
binding upon, nor shall resort for the enforcement thereof be had to, the
property of any of its shareholders, trustees, officers, employees or agents,
regardless of whether such obligation or liability is in the nature of contract,
tort or otherwise.

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     IN WITNESS WHEREOF, each of the undersigned has executed this Agreement, or
caused this Agreement to be duly executed on its behalf, as of the date first
set forth above.


                         SECURITY CAPITAL ATLANTIC INCORPORATED
                                                                          
                                                                          
                         By:   /s/ James C. Potts                         
                               ------------------                         
                               James C. Potts                             
                               Co-Chairman                                
                                                                          
                         SECURITY CAPITAL PACIFIC TRUST                   
                                                                          
                                                                          
                         By:   /s/ C. Ronald Blankenship                  
                               -------------------------                  
                               C. Ronald Blankenship                      
                               Chairman                                   
                                                                          
                         SECURITY CAPITAL GROUP INCORPORATED              
                                                                          
                                                                          
                         By:   /s/ Jeffrey A. Klopf                       
                               --------------------                       
                               Jeffrey A. Klopf                           
                               Senior Vice President                      
                                                                          
                         HOMESTEAD VILLAGE INCORPORATED                   
                                                                          
                                                                          
                         By:   /s/ David C. Dressler, Jr.                 
                               --------------------------                 
                               David C. Dressler, Jr.                     
                               Chairman                                   

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