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                                                                    EXHIBIT 10.1


                       SECURITY CAPITAL GROUP INCORPORATED
                               125 LINCOLN AVENUE
                           SANTA FE, NEW MEXICO 87501

                                January 17, 2002


Storage USA, Inc.
Storage USA Trust
SUSA Partnership, L.P.
c/o Storage USA, Inc.
175 Toyota Plaza, Suite 700
Memphis, Tennessee  38103


     Re:      Purchase and Sale Agreement, dated as of December 5, 2001, by and
              among Storage USA, Inc., a Tennessee corporation ("Storage USA"),
              Storage USA Trust, a Maryland real estate investment trust and a
              wholly owned subsidiary of the Company, SUSA Partnership, L.P., a
              Tennessee limited partnership of which Storage USA is the sole
              general partner, and Security Capital Group Incorporated, a
              Maryland corporation ("Security Capital") (the "Purchase
              Agreement")


Ladies and Gentlemen:

         This is to confirm that, in connection with the Memorandum of
Understanding, dated January 17, 2002 (a copy of which is attached hereto),
entered into on behalf of the parties to the litigation referred to therein by
their respective attorneys (the "MOU"), and in consideration of the settlement
set forth in the MOU, all references in the Purchase Agreement to $42.00 -
including without limitation in Sections 1.116 (definition of "Share
Consideration"), Section 1.140 (definition of "Unit Consideration"), Section
2.2(a) (Purchase Consideration; Redemption), and Section 5.6(g) (No
Solicitation--definition of "Superior Transaction") - shall for all purposes be
deemed references to $42.50, and the words "not to exceed $128,197,920" in
Section 2.7(a)(iii) shall be deleted, in each case, effective as of the date
hereof and of the MOU.

         In all respect not inconsistent with the terms and provisions of this
letter agreement, the Purchase Agreement shall continue in full force and effect
in accordance with the terms and conditions thereof. From and after the date
hereof, each reference to the Purchase Agreement in any other instrument or
document shall be deemed a reference to the Purchase Agreement as amended
hereby, unless the context otherwise requires.



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                                         Very truly yours,

                                         SECURITY CAPITAL GROUP INCORPORATED

                                         By:   /s/ C. Ronald Blankenship
                                            ------------------------------------
                                              Name: C. Ronald Blankenship
                                              Title: Vice Chairman and
                                                     Chief Operating Officer

Accepted and agreed:

STORAGE USA, INC.

By: /s/ Dean Jernigan
    ----------------------------------------
       Name: Dean Jernigan
       Title: Chairman, Chief Executive
              Officer and President


STORAGE USA TRUST

By: /s/ Dean Jernigan
    ----------------------------------------
      Name: Dean Jernigan
      Title: Chairman, Chief Executive
             Officer and President


SUSA PARTNERSHIP, L.P.

By: /s/ Dean Jernigan
    ----------------------------------------
      Name: Dean Jernigan
      Title: Chairman, Chief Executive
             Officer and President