EXHIBIT 10.6


  AMENDMENT TO MASTER LEASE AND SECURITY AGREEMENT AND UNCONDITIONAL GUARANTY

      THIS AMENDMENT (this "AMENDMENT"), dated as of March 15, 2002, is entered
into among IRON MOUNTAIN STATUTORY TRUST - 2001, a Connecticut statutory trust
(the "LESSOR"), IRON MOUNTAIN INFORMATION MANAGEMENT, INC. (f/k/a Iron Mountain
Records Management, Inc.), a Delaware corporation (the "LESSEE") and IRON
MOUNTAIN INCORPORATED, a Pennsylvania corporation (the "GUARANTOR").

                               W I T N E S S E T H :

      WHEREAS, the Lessor and the Lessee have heretofore entered into a Master
Lease and Security Agreement, dated as of May 22, 2001, as amended by Amendment
No. 1 dated as of November 1, 2001 (the "LEASE"); and

      WHEREAS, the Guarantor has executed and delivered an Unconditional
Guaranty dated as of May 22, 2001 (the "GUARANTY") in favor of the Lessor; and

      WHEREAS, the Lessee and the Guarantor have requested that the Lease and
the Guaranty be amended in certain respects, and the Lessor has indicated its
willingness to consent to such amendments;

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

      1. DEFINITIONS. Capitalized terms used but not otherwise defined in
this Amendment have the meanings specified in Appendix 1 to the Lease; and
the rules of interpretation set forth in Appendix 1 shall apply to this
Amendment.

      2. AMENDMENT TO LEASE. The definition of "Iron Mountain Credit Agreement"
in Appendix 1 of the Lease is hereby amended in full to read as follows:

            "IRON MOUNTAIN CREDIT AGREEMENT" means the Fifth Amended and
      Restated Credit Agreement dated as of March 15, 2002, among the Guarantor,
      Iron Mountain Canada Corporation, the lenders from time to time parties
      thereto, The Chase Manhattan Bank of Canada, as Canadian Administrative
      Agent, and The Chase Manhattan Bank, as Administrative Agent, as amended,
      amended and restated, modified, extended, refinanced or supplemented from
      time to time (except as otherwise specified in any Operative Document).

      3. AMENDMENTS TO GUARANTY. The Guaranty is hereby amended as follows:

            (a) Section 10 of the Guaranty is amended by adding a new last
paragraph thereto to read as follows:



            Any financial statement required to be delivered pursuant to this
      Section 10 shall be deemed to have been delivered on the date on which the
      Guarantor posts such financial statement on the Intralinks website on the
      Internet at WWW.INTRALINKS.COM; provided that the Guarantor shall give
      notice of any such posting (together with access instructions therefor) to
      the Lessor, each Equity Participant and the Administrative Agent (and the
      Administrative Agent shall then give notice of any such posting (with such
      access instructions) to the Lenders). Notwithstanding the foregoing, the
      Guarantor shall deliver paper copies of any financial statement referred
      to in this Section 10 to the Administrative Agent if the Administrative
      Agent or any Lender requests the Guarantor to deliver such paper copies
      until written notice to cease delivering such paper copies is given by the
      Administrative Agent.

            (b) The Leverage Ratio grid set forth in Section 11(a)(i) of the
Guaranty is amended in full to read as follows:

      ------------------------------------------------------------------
      PERIOD                                             LEVERAGE RATIO
      ------------------------------------------------------------------
      From July 1, 2001 through March 31, 2002             5.50 to 1
      ------------------------------------------------------------------
      From April 1, 2002 through December 31, 2002         5.65 to 1
      ------------------------------------------------------------------
      From January 1, 2003 through March 31, 2003          5.55 to 1
      ------------------------------------------------------------------
      From April 1, 2003 through June 30, 2003             5.45 to 1
      ------------------------------------------------------------------
      From July 1, 2003 through September 30, 2003         5.35 to 1
      ------------------------------------------------------------------
      From October 1, 2003 through December 31, 2003       5.25 to 1
      ------------------------------------------------------------------
      From January 1, 2004 and at all times thereafter     5.00 to 1
      ------------------------------------------------------------------


            (c) The Interest Coverage Ratio grid set forth in Section 11(a)(ii)
of the Guaranty is amended in full to read as follows:

      ------------------------------------------------------------------
      PERIOD                                         INTEREST COVERAGE
                                                            RATIO
      ------------------------------------------------------------------
      From July 1, 2001 through June 30, 2003               2.00
      ------------------------------------------------------------------
      From July 1, 2003 through September 30, 2003          2.10
      ------------------------------------------------------------------
      From October 1, 2003 through December 31,             2.15
      2003
      ------------------------------------------------------------------
      From January 1, 2004 through June 30, 2004            2.25
      ------------------------------------------------------------------
      From July 1, 2004 through September 30, 2004          2.35
      ------------------------------------------------------------------
      From October 1, 2004 and at all times                 2.50
      thereafter
      ------------------------------------------------------------------

            (d) Section 11(a)(iv)(iv)(B) of the Guaranty is amended by replacing
the amount "$3,000,000" set forth therein with the amount "$10,000,000".

            (e)   Section 13(a)(i) of the Guaranty is amended in full to read
as follows:

      "(i) is a corporation duly organized, validly existing and in good
      standing under the laws of the jurisdiction of its organization, and"


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      4. CONSENT TO REINCORPORATION. Nothing in any Operative Document shall, or
shall be deemed to, prohibit or restrict the merger of the Guarantor with or
into another corporation for the sole purpose of changing the Guarantor's
domicile from Pennsylvania to Delaware, so long as the surviving corporation of
such merger, if such surviving corporation is not the Guarantor, shall expressly
assume, in writing, the obligations of the Guarantor under the Guaranty and any
other Operative Documents to which it is a party, and expressly agree in writing
to be bound by all other provisions applicable to the Guarantor under the
Guaranty and such other Operative Documents in a manner reasonably satisfactory
to the Administrative Agent.

      5. CONDITION TO EFFECTIVENESS. This Amendment shall become effective as of
the date hereof when the Administrative Agent shall have received counterparts
of this Amendment executed by the Lessor, the Lessee, the Guarantor, and the
Collateral Agent.

      6. REPRESENTATIONS AND WARRANTIES. As of the date hereof, each of the
Lessee and the Guarantor hereby represents and warrants to Lessor, the
Administrative Agent and the Lenders that:

            (a) the representations and warranties made by it in each Operative
Document to which it is a party are true and correct in all material respects on
and as of the date hereof as though made on and as of such date, except to the
extent such representations and warranties relate solely to an earlier date, in
which case such representations and warranties shall be true and correct on and
as of such earlier date; and

            (b) no event has occurred and is continuing under any Operative
Document that constitutes a Default or an Event of Default.

      7. COUNTERPARTS. This Amendment may be executed in several counterparts
and by the different parties hereto on separate counterparts, all of which taken
together shall constitute but one and the same Amendment. Delivery of an
executed counterpart of a signature page of this Amendment by telecopy shall be
effective as delivery of a manually executed counterpart of this Amendment.

      8. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

      9. OPERATIVE DOCUMENTS REMAIN IN EFFECT. Except as provided herein, all
provisions, terms and conditions of the Operative Documents shall remain in full
force and effect. As amended hereby, the Operative Documents are ratified and
confirmed in all respects.


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      IN WITNESS WHEREOF, the parties have caused this Amendment to be duly
executed and delivered as of the date first above written.

                              IRON MOUNTAIN STATUTORY TRUST - 2001,
                              as Lessor
                              By:   First Union National Bank,
                                    not in its individual capacity, except as
                                    expressly provided herein, but solely as
                                    trustee

                              By: /s/ Evangelos Ntavos
                                  --------------------------------------
                                  Evangelos Ntavos
                                  Trust officer

                              IRON MOUNTAIN INFORMATION
                              MANAGEMENT, INC. (f/k/a Iron Mountain Records
                              Management, Inc.), as Lessee

                              By: /s/ JP Lawrence
                                  --------------------------------------
                                  JP Lawrence
                                  VP and Treasurer


                              IRON MOUNTAIN INCORPORATED,
                              as Guarantor

                              By: /s/ JP Lawrence
                                  --------------------------------------
                                  JP Lawrence
                                  VP and Treasurer


      Consented to and Agreed:


      THE BANK OF NOVA SCOTIA,
      as Collateral Agent


      By: /s/ T.M. Pitcher
          -------------------------------
          T.M. Pitcher
          Authorized Signatory


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