Exhibit 4.15

                              DECLARATION OF TRUST
                                       OF
                               IM CAPITAL TRUST I

         THIS  DECLARATION  OF  TRUST,  dated  as of  December  10,  2001  (this
"Declaration  of Trust"),  is made by and among Iron  Mountain  Incorporated,  a
Pennsylvania  corporation,  as  sponsor  (the  "Sponsor"),  The Bank of New York
(Delaware), a Delaware banking corporation, as trustee (the "Delaware Trustee"),
The Bank of New York, a New York banking corporation,  as trustee (the "Property
Trustee"), and John P. Lawrence, as trustee (the "Regular Trustee" and, together
with the Delaware Trustee and the Property Trustee, the "Trustees"). The Sponsor
and the Trustees hereby agree as follows:

         1. The trust created hereby shall be known as "IM Capital Trust I" (the
"Trust"),  in which name the  Trustees or the  Sponsor,  to the extent  provided
herein, may conduct the business of the Trust, make and execute  contracts,  and
sue and be sued.

         2. The Sponsor hereby assigns, transfers,  conveys and sets over to the
Trust the sum of $10.  The Trust hereby  acknowledges  receipt of such amount in
trust from the Sponsor,  which amount shall constitute the initial trust estate.
The  Trustees  hereby  declare that they will hold the trust estate in trust for
the Sponsor.  It is the  intention of the parties  hereto that the Trust created
hereby  constitute a business trust under Chapter 38 of Title 12 of the Delaware
Code,  12 Del. C. ss. 3801, et seq. (the  "Business  Trust Act"),  and that this
document  constitutes  the governing  instrument of the Trust.  The Trustees are
hereby  authorized  and directed to execute and file a certificate of trust with
the  Delaware  Secretary  of State in  accordance  with  the  provisions  of the
Business Trust Act.

         3. The Sponsor and the Trustees will enter into an amended and restated
Declaration of Trust,  satisfactory to each such party and  substantially in the
form to be included  as an exhibit to the 1933 Act  Registration  Statement  (as
defined below),  to provide for the contemplated  operation of the Trust created
hereby and the  issuance  of the trust  preferred  securities  of the Trust (the
"Preferred Securities") and the trust common securities of the Trust referred to
therein.  Prior to the  execution  and  delivery of such  amended  and  restated
Declaration  of  Trust,  the  Trustees  shall  not have  any duty or  obligation
hereunder or with respect to the trust estate,  except as otherwise  required by
applicable  law or as may be  necessary to obtain  prior to such  execution  and
delivery any  licenses,  consents or  approvals  required by  applicable  law or
otherwise.

         4. The Sponsor,  as the sponsor of the Trust, is hereby authorized,  in
its  discretion,  (i) to  prepare  and file  with the  Securities  and  Exchange
Commission  (the  "Commission")  and to  execute,  in each case on behalf of the
Trust, (a) the Registration Statement on Form S-3 or other appropriate form (the
"1933 Act  Registration  Statement"),  including the prospectus and the exhibits
included therein, any pre-effective or post-effective amendments thereto and any
registration  statements filed subsequent  thereto under Rule 462(b) promulgated
under the Securities  Act of 1933, as amended (the "1933 Act"),  relating to the
registration  under the 1933 Act of the Preferred  Securities  and certain other
securities,  (b) any preliminary  prospectus or prospectus or supplement thereto
relating to the Preferred  Securities  required to be filed pursuant to the 1933
Act, and (c) a Registration Statement on Form 8-A or other appropriate form (the
"1934  Act   Registration   Statement"),   including   all   pre-effective   and
post-effective amendments thereto, relating to the registration of the Preferred
Securities  under the  Securities  Exchange  Act of 1934,  as amended (the "1934
Act"), and such other documents, forms or filings as may be required by the 1933
Act, the 1934 Act, or the Trust Indenture
<PAGE>


Act of 1939, as amended, in each case relating to the Preferred Securities; (ii)
to prepare and file with the New York Stock Exchange or other exchange (each, an
"Exchange")  or the National  Association  of  Securities  Dealers  ("NASD") and
execute on behalf of the Trust a listing  application  or  applications  and all
other applications,  statements, certificates,  agreements and other instruments
as shall be  necessary  or desirable  to cause the  Preferred  Securities  to be
listed on any such  Exchange  or the NASD's  Nasdaq  National  Market;  (iii) to
prepare,  file and  execute on behalf of the Trust such  applications,  reports,
surety  bonds,  irrevocable  consents,  appointments  of attorney for service of
process and other papers and  documents as the Sponsor,  on behalf of the Trust,
may deem  necessary or desirable to register,  or establish the  exemption  from
registration  of, the Preferred  Securities  under the  securities or "Blue Sky"
laws of such  jurisdictions  as the  Sponsor,  on behalf of the Trust,  may deem
necessary or desirable;  (iv) to execute and deliver letters or documents to, or
instruments for filing with, a depository relating to the Preferred  Securities;
and (v) to negotiate the terms of, and execute, deliver and perform on behalf of
the Trust, one or more  underwriting  agreements with one or more  underwriters,
purchase  agreements,  dealer manager  agreements,  escrow  agreements and other
documents and agreements, in each case relating to the offering of the Preferred
Securities  as the  Sponsor,  on  behalf of the  Trust,  may deem  necessary  or
desirable.  In the event that any filing  referred to in clauses  (i),  (ii) and
(iii) above is  required by the rules and  regulations  of the  Commission,  any
Exchange,  the NASD or state  securities  or "Blue Sky" laws,  to be executed on
behalf of the Trust by one or more of the Trustees, any of the Regular Trustees,
in their capacity as trustees of the Trust, are hereby authorized to join in any
such filing and to execute on behalf of the Trust any and all of the  foregoing,
it being understood that the Regular Trustees,  in their capacity as trustees of
the Trust, shall not be required to join in any such filing or execute on behalf
of the Trust any such document  unless  required by the rules and regulations of
the Commission, any Exchange, the NASD or state securities or "Blue Sky" laws.

         5.  This   Declaration  of  Trust  may  be  executed  in  one  or  more
counterparts.

         6. The number of trustees of the Trust initially shall be three (3) and
thereafter  the number of trustees of the Trust shall be such number as shall be
fixed from time to time by a written  instrument signed by the Sponsor which may
increase or decrease  the number of  trustees of the Trust;  provided,  however,
that to the extent  required by the Business Trust Act, one trustee of the Trust
shall either be a natural  person who is a resident of the State of Delaware or,
if not a natural person,  an entity which has its principal place of business in
the State of  Delaware  and  otherwise  meets  the  requirements  of  applicable
Delaware law.  Subject to the  foregoing,  the Sponsor is entitled to appoint or
remove  without  cause any trustee of the Trust at any time.  Any trustee of the
Trust may resign upon thirty  (30) days' prior  notice to the Sponsor  provided,
however, such notice shall not be required if it is waived by the Sponsor.

         7. The Delaware Trustee, in its capacity as trustee of the Trust, shall
not have any of the powers or duties of the Trustees set forth herein (except as
may be  required  under the  Business  Trust  Act) and shall be a trustee of the
Trust for the sole and limited purpose of fulfilling the requirements of Section
3807 of the Business Trust Act.

         8. The Sponsor  hereby  agrees to (i)  reimburse  the  Trustees for all
reasonable expenses (including reasonable fees and expenses of counsel and other
experts),  and (ii) indemnify,  defend and hold harmless the Trustees and any of
the officers, directors,  employees and agents of the Trustees (the "Indemnified
Persons")  from and against any and all losses,  damages,  liabilities,  claims,
actions,  suits, costs, expenses,  disbursements  (including the reasonable fees
and expenses of counsel),  taxes and penalties of any kind and nature whatsoever
(collectively, "Expenses"), to the extent that such Expenses arise out of or are
imposed upon or asserted at any time against such
<PAGE>

Indemnified  Persons  with respect to the  performance  of this  Declaration  of
Trust,  the creation,  operation or termination of the Trust or the transactions
contemplated hereby;  provided,  however, that the Sponsor shall not be required
to indemnify any  Indemnified  Person for any Expenses which are a result of the
willful misconduct, bad faith or gross negligence of such Indemnified Person.

         9. The Trust may be dissolved and terminated before the issuance of the
Preferred Securities at the election of the Sponsor.

         10. This  Declaration  of Trust shall be governed by, and  construed in
accordance  with, the laws of the State of Delaware  (without regard to conflict
of laws principles).


<PAGE>


         IN WITNESS WHEREOF,  the parties hereto have caused this Declaration of
Trust to be duly executed as of the day and year first above written.

                                      IRON MOUNTAIN INCORPORATED,
                                      as Sponsor


                                      By:     /s/ John P. Lawrence
                                      Name:   John P. Lawrence
                                      Title:  Vice President and Treasurer


                                      THE BANK OF NEW YORK (DELAWARE),
                                      as Delaware Trustee


                                      By:     /s/ William T. Lewis
                                      Name:   William T. Lewis
                                      Title:  Senior Vice President


                                      THE BANK OF NEW YORK,
                                      as Property Trustee


                                      By:     /s/ Kisha A. Holder
                                      Name:   Kisha A. Holder
                                      Title:  Assistant Treasurer



                                      /s/ John P. Lawrence
                                      JOHN P. LAWRENCE,
                                      as Regular Trustee