<SUBMISSION>
<ACCESSION-NUMBER>0001047469-04-011628
<TYPE>S-8
<PUBLIC-DOCUMENT-COUNT>5
<FILING-DATE>20040412
<EFFECTIVENESS-DATE>20040412
<FILER>
<COMPANY-DATA>
<CONFORMED-NAME>IRON MOUNTAIN INC/PA
<CIK>0001020569
<ASSIGNED-SIC>4220
<IRS-NUMBER>232588479
<STATE-OF-INCORPORATION>PA
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>S-8
<ACT>33
<FILE-NUMBER>333-114398
<FILM-NUMBER>04728515
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>745 ATLANTIC AVENUE
<CITY>BOSTON
<STATE>MA
<ZIP>02111
<PHONE>6175354766
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>745 ATLANTIC AVENUE
<CITY>BOSTON
<STATE>MA
<ZIP>02111
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>PIERCE LEAHY CORP
<DATE-CHANGED>19960807
</FORMER-COMPANY>
</FILER>
<DOCUMENT>
<TYPE>S-8
<SEQUENCE>1
<FILENAME>a2133163zs-8.htm
<DESCRIPTION>FORM S-8
<TEXT>
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<P ALIGN="CENTER"><FONT SIZE=5><B>UNITED STATES<BR>
SECURITIES AND EXCHANGE COMMISSION<BR>  </B></FONT><FONT SIZE=2><B>WASHINGTON, D.C. 20549  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=5><B>FORM S-8<BR>  </B></FONT><FONT SIZE=2><B>REGISTRATION STATEMENT UNDER THE<BR>
SECURITIES ACT OF 1933  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=5><B>IRON MOUNTAIN INCORPORATED<BR>  </B></FONT><FONT SIZE=2>(Exact name of registrant as specified in its charter) </FONT></P>

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<TD WIDTH="49%" ALIGN="CENTER"><FONT SIZE=2><B>Pennsylvania</B></FONT><FONT SIZE=2><BR>
(State or Other Jurisdiction of<BR>
Incorporation or Organization)</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="49%" ALIGN="CENTER"><FONT SIZE=2><B>23-2588479</B></FONT><FONT SIZE=2><BR>
(I.R.S. Employer<BR>
Identification No.)</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD COLSPAN=3 ALIGN="CENTER" VALIGN="TOP"><BR><FONT SIZE=2><B>745 Atlantic Avenue, Boston, Massachusetts 02111</B></FONT><FONT SIZE=2><BR>
(Address of Principal Executive Offices including zip code)</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD COLSPAN=3 ALIGN="CENTER" VALIGN="TOP"><BR><FONT SIZE=2><B>The Iron Mountain Companies 401(k) Plan</B></FONT><FONT SIZE=2><BR>
(Full Title of the Plan)</FONT></TD>
</TR>
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<TD WIDTH="49%" ALIGN="CENTER"><FONT SIZE=2><BR>
C. Richard Reese<BR>
Chairman of The Board of<BR>
Directors and Chief Executive Officer<BR>
Iron Mountain Incorporated<BR>
745 Atlantic Avenue<BR>
Boston, Massachusetts 02111<BR>
(617) 535-4766</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="49%" ALIGN="CENTER"><BR><FONT SIZE=2><B>COPY TO:</B></FONT><FONT SIZE=2><BR>
William J. Curry, Esq.<BR>
Sullivan &amp; Worcester LLP<BR>
One Post Office Square<BR>
Boston, Massachusetts 02109<BR>
(617) 338-2800</FONT></TD>
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<TD COLSPAN=3 ALIGN="CENTER"><FONT SIZE=2><BR>
(Name, Address and Telephone Number of Agent For Service)</FONT></TD>
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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In addition, pursuant to Rule&nbsp;416(c) under the Securities Act of 1933, this registration statement also covers an indeterminate amount of interests to be
offered or sold pursuant to the employee benefit plan described herein. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;If,
as a result of stock splits, stock dividends or similar transactions, the number of securities purported to be registered on this registration statement changes, the provisions of
Rule&nbsp;416 under the Securities Act of 1933, as amended, shall apply to this registration statement. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>CALCULATION OF REGISTRATION FEE  </B></FONT></P>

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<TH WIDTH="29%" ALIGN="CENTER"><FONT SIZE=1><B>Title of Each Class of<BR>
Securities to be Registered</B></FONT><BR></TH>
<TH WIDTH="1%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="14%" ALIGN="CENTER"><FONT SIZE=1><B>Amount to be<BR>
Registered</B></FONT><BR></TH>
<TH WIDTH="1%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="19%" ALIGN="CENTER"><FONT SIZE=1><B>Proposed Maximum<BR>
Offering Price<BR>
Per Unit(1)</B></FONT><BR></TH>
<TH WIDTH="1%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="19%" ALIGN="CENTER"><FONT SIZE=1><B>Proposed Maximum<BR>
Aggregate<BR>
Offering Price(2)</B></FONT><BR></TH>
<TH WIDTH="1%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="16%" ALIGN="CENTER"><FONT SIZE=1><B>Amount of<BR>
Registration Fee</B></FONT><BR></TH>
</TR>
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<TD COLSPAN=9><HR NOSHADE></TD>
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<TD WIDTH="29%"><FONT SIZE=2>Common Stock, $0.01 par value per share</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER"><FONT SIZE=2>500,000</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER"><FONT SIZE=2>$44.06</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER"><FONT SIZE=2>$22,030,000</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="16%" ALIGN="CENTER"><FONT SIZE=2>$2,791.20</FONT></TD>
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<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(1)</FONT></DT><DD><FONT SIZE=2>The
proposed maximum offering price per share and the proposed maximum aggregate offering price have been estimated solely for the purpose of calculating the amount of the
registration fee in accordance with Rules&nbsp;457(c) and 457(h) under the Securities Act of 1933 on the basis of the average of the high and low prices of the Common Stock on the New York Stock
Exchange on April&nbsp;8, 2004. </FONT></DD></DL>
<BR>

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<A NAME="toc_ca1472_1"> </A>
<BR></FONT><FONT SIZE=2><B>PART I&#151;INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS    <BR>    </B></FONT></P>

<P><FONT SIZE=2><A
NAME="ca1472_item_1._plan_information;_item__ite03513"> </A>
<A NAME="toc_ca1472_2"> </A></FONT> <FONT SIZE=2><B>Item 1. Plan Information; Item 2. Registrant Information and Employee Plan Annual Information.    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The documents containing the information required by these items will be given to employees participating in The Iron Mountain Companies 401(k) Plan (the "Plan")
and are not required to be filed with the Securities and Exchange Commission as part of the registration statement or as an exhibit thereto. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Employees
participating in the Plan may obtain a copy of the Plan or the documents incorporated by reference in Item 3 of Part&nbsp;II below, at no cost, by writing or telephoning us
at: 745 Atlantic Avenue, Boston, Massachusetts 02111, (617)&nbsp;535-4799, Attention: Investor Relations. These documents are also incorporated by reference in the Section&nbsp;10(a)
prospectus. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ca1472_part_ii_#151;information_requi__par02343"> </A>
<A NAME="toc_ca1472_3"> </A>
<BR></FONT><FONT SIZE=2><B>PART II&#151;INFORMATION REQUIRED IN THE REGISTRATION STATEMENT    <BR>    </B></FONT></P>

<P><FONT SIZE=2><A
NAME="ca1472_item_3._incorporation_of_documents_by_reference."> </A>
<A NAME="toc_ca1472_4"> </A></FONT> <FONT SIZE=2><B>Item 3. Incorporation of Documents by Reference.    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The following additional documents, which have been filed by the Company with the Securities and Exchange Commission (the "Commission"), are incorporated by
reference in and made a part of this registration statement, as of their respective dates: </FONT></P>

<UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(a)</FONT></DT><DD><FONT SIZE=2>The
Company's Annual Report on Form&nbsp;10-K for the fiscal year ended December&nbsp;31, 2003 filed on March&nbsp;11, 2004;
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(b)</FONT></DT><DD><FONT SIZE=2>The
Company's Current Reports on Form&nbsp;8-K filed January&nbsp;7, 2004 and January&nbsp;16, 2004; and
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(c)</FONT></DT><DD><FONT SIZE=2>The
description of the Company's common stock contained in the registration statement on Form&nbsp;8-A dated May&nbsp;27, 1997 (File No.&nbsp;1-13045),
including all amendments or reports filed for the purpose of updating such description. </FONT></DD></DL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;All
documents subsequently filed by the Company, the Plan, or both pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended, prior to the filing
of a post-effective amendment which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by
reference in this registration statement and to be part hereof from the date of filing of such documents. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Any
statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this registration
statement to the extent that a statement herein, or in any subsequently filed document which also is or is deemed to be incorporated by reference, modifies or supersedes such statement. Any statement
so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this registration statement. </FONT></P>

<P><FONT SIZE=2><A
NAME="ca1472_item_4._description_of_securities."> </A>
<A NAME="toc_ca1472_5"> </A>
<BR></FONT><FONT SIZE=2><B>Item 4. Description of Securities.    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Not applicable. </FONT></P>

<P><FONT SIZE=2><A
NAME="ca1472_item_5._interests_of_named_experts_and_counsel."> </A>
<A NAME="toc_ca1472_6"> </A>
<BR></FONT><FONT SIZE=2><B>Item 5. Interests of Named Experts and Counsel.    <BR>    </B></FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Not applicable. </FONT></P>

<P><FONT SIZE=2><A
NAME="ca1472_item_6._indemnification_of_directors_and_officers."> </A>
<A NAME="toc_ca1472_7"> </A>
<BR></FONT><FONT SIZE=2><B>Item 6. Indemnification of Directors and Officers.    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;As permitted by the Pennsylvania Business Corporation Law of 1988, as amended ("PBCL"), the Company's bylaws provide that a director shall not be
personally liable for monetary damages for any action taken, or any failure to take any action, unless the director breaches or fails to perform the </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>2</FONT></P>

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<P><FONT SIZE=2>duties
of his office under the PBCL and such breach or failure to perform constitutes self-dealing, willful misconduct or recklessness. These provisions of the Company's bylaws, however,
do not apply to the responsibility or liability of a director pursuant to any criminal statute, or to the liability of a director for the payment of taxes pursuant to local, state or federal law.
These provisions offer persons who serve on the board of directors protection against awards of monetary damages for negligence in the performance of their duties. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
Company's bylaws also provide that directors or officers made a party to, or threatened to be made a party to, or otherwise involved in, any proceeding, because he or she is or was a
representative of the Company or is or was serving as a representative of another corporation or any partnership, joint venture, trust, employee benefit plan or other enterprise, on the Company's
behalf, shall be indemnified and held harmless by the Company to the fullest extent permitted by Pennsylvania law against all expenses, liabilities and losses reasonably incurred by or imposed upon
him or her, in connection with any threatened, pending or completed action, suit or proceeding if such person acted in good faith and in a manner such person reasonably believed to be in, or not
opposed to, the best interests of the Company and, with respect to any criminal proceeding, had no reasonable cause to believe that his or her conduct was unlawful. Indemnification is not available,
however, if a court determines that the act or failure to act giving rise to the claim constitutes willful misconduct or recklessness. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant
to the Company's bylaws, amending the provisions to reduce the limitation of director's liability or limit the right to indemnification requires unanimous vote of the directors
or a majority vote of the shareholders. </FONT></P>

<P><FONT SIZE=2><A
NAME="ca1472_item_7._exemption_from_registration_claimed."> </A>
<A NAME="toc_ca1472_8"> </A>
<BR></FONT><FONT SIZE=2><B>Item 7. Exemption from Registration Claimed.    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Not Applicable. </FONT></P>

<P><FONT SIZE=2><A
NAME="ca1472_item_8._exhibits."> </A>
<A NAME="toc_ca1472_9"> </A>
<BR></FONT><FONT SIZE=2><B>Item 8. Exhibits.    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The Company has submitted the Plan to the Internal Revenue Service ("IRS") in a timely manner, and undertakes to submit any amendments thereto to the IRS in a
timely manner. The Company further undertakes to make all changes required by the IRS in order to qualify the Plan under Section&nbsp;401 of the Internal Revenue Code. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ca1472_exhibit_index"> </A>
<A NAME="toc_ca1472_10"> </A>
<BR></FONT><FONT SIZE=2><B>EXHIBIT INDEX    <BR>    </B></FONT></P>

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<TH WIDTH="11%" ALIGN="LEFT"><FONT SIZE=1><B>EXHIBIT NO.<BR> </B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="86%" ALIGN="CENTER"><FONT SIZE=1><B>DESCRIPTION</B></FONT><HR NOSHADE></TH>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="11%" ALIGN="RIGHT"><FONT SIZE=2>5.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="86%"><FONT SIZE=2>Opinion of Sullivan&nbsp;&amp; Worcester LLP.*</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="11%" ALIGN="RIGHT"><FONT SIZE=2>5.2</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="86%"><FONT SIZE=2>Opinion of Ballard Spahr Andrews&nbsp;&amp; Ingersoll, LLP.*</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="11%" ALIGN="RIGHT"><FONT SIZE=2>23.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="86%"><FONT SIZE=2>Consent of Sullivan&nbsp;&amp; Worcester LLP (contained in the opinion of Sullivan&nbsp;&amp; Worcester LLP filed herewith as Exhibit&nbsp;5.1).</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="11%" ALIGN="RIGHT"><FONT SIZE=2>23.2</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="86%"><FONT SIZE=2>Consent of Ballard Spahr Andrews&nbsp;&amp; Ingersoll, LLP (contained in the opinion of Ballard Spahr Andrews&nbsp;&amp; Ingersoll, LLP filed herewith as Exhibit&nbsp;5.2).</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="11%" ALIGN="RIGHT"><FONT SIZE=2>23.3</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="86%"><FONT SIZE=2>Independent Auditors' Consent Deloitte&nbsp;&amp; Touche LLP (Iron Mountain Incorporated).*</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="11%" ALIGN="RIGHT"><FONT SIZE=2>23.4</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="86%"><FONT SIZE=2>Independent Auditors' Consent RSM Robson Rhodes LLP (Iron Mountain Europe Limited).*</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="11%" ALIGN="RIGHT"><FONT SIZE=2>24</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="86%"><FONT SIZE=2>Powers of Attorney (included in the signature page to this registration statement).</FONT></TD>
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<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>*</FONT></DT><DD><FONT SIZE=2>filed
herewith </FONT></DD></DL>
<P ALIGN="CENTER"><FONT SIZE=2>3</FONT></P>

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<P><FONT SIZE=2><A
NAME="ca1472_item_9._undertakings."> </A>
<A NAME="toc_ca1472_11"> </A>
<BR></FONT><FONT SIZE=2><B>Item 9. Undertakings.    <BR>    </B></FONT></P>

<UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(a)</FONT></DT><DD><FONT SIZE=2>The
undersigned registrant hereby undertakes:
<BR><BR></FONT>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(1)</FONT></DT><DD><FONT SIZE=2>To
file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:
<BR><BR></FONT>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(i)</FONT></DT><DD><FONT SIZE=2>To
include any prospectus required by Section&nbsp;10(a)(3) of the Securities Act of 1933;
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(ii)</FONT></DT><DD><FONT SIZE=2>To
reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment
thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this registration statement. Notwithstanding the foregoing, any increase or decrease in
volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering
range may be reflected in the form of prospectus filed with the Commission pursuant to Rule&nbsp;424(b) under the Securities Act of 1933 if, in the aggregate, the changes in volume and price
represent no more than a 20&nbsp;percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement; and
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(iii)</FONT></DT><DD><FONT SIZE=2>To
include any material information with respect to the plan of distribution not previously disclosed in this registration statement or any material change to such
information in this registration statement; </FONT></DD></DL>
</DD></DL>
</DD></DL>
</UL>
<UL>
<UL>

<P><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that subparagraphs (a)(1)(i)&nbsp;and (a)(1)(ii)&nbsp;do not apply if the information required to be included in a
post-effective amendment by those paragraphs is contained in the periodic reports filed with or furnished to the Commission by the Company pursuant to Section&nbsp;13 or
Section&nbsp;15(d) of the Exchange Act of 1934, that are incorporated by reference in this registration statement. </FONT></P>

<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(2)</FONT></DT><DD><FONT SIZE=2>That,
for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial </FONT><FONT SIZE=2><I>bona fide</I></FONT><FONT SIZE=2> offering
thereof.
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(3)</FONT></DT><DD><FONT SIZE=2>To
remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.
<BR><BR></FONT></DD></DL>
</UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(b)</FONT></DT><DD><FONT SIZE=2>The
undersigned registrant hereby further undertakes that, for the purposes of determining any liability under the Securities Act of 1933, each filing of the Company's annual report
pursuant to Section&nbsp;13(a) or Section&nbsp;15(d) of the Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section&nbsp;15(d) of
the Exchange Act of 1934) that is incorporated by reference in this registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial </FONT><FONT SIZE=2><I>bona fide</I></FONT><FONT SIZE=2> offering thereof.
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(c)</FONT></DT><DD><FONT SIZE=2>Insofar
as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the
provisions described under Item 6 of this registration statement, or otherwise, the registrant has been advised that in the opinion of the Commission such indemnification is against public policy as
expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses
incurred or paid by a director, officer or controlling person of the </FONT></DD></DL>
</UL>
<P ALIGN="CENTER"><FONT SIZE=2>4</FONT></P>

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<UL>
<UL>

<P><FONT SIZE=2>registrant
in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant
will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is
against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue. </FONT></P>

</UL>
</UL>
<P ALIGN="CENTER"><FONT SIZE=2>5</FONT></P>

<HR NOSHADE>
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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="jc1472_signatures"> </A>
<A NAME="toc_jc1472_1"> </A>
<BR></FONT><FONT SIZE=2><B>SIGNATURES    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to the requirements of the Securities Act of 1933, the Company certifies that it has reasonable grounds to believe that it meets all of the requirements
for filing on Form&nbsp;S-8 and has duly caused this Registration Statement on Form&nbsp;S-8 to be signed on its behalf by the undersigned, thereunto duly authorized, in
the City of Boston, Commonwealth of Massachusetts, on the 12th day of April, 2004. </FONT></P>

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<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2><B>IRON MOUNTAIN INCORPORATED</B></FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><B><BR>
&nbsp;</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%"><BR><FONT SIZE=2>By:</FONT></TD>
<TD WIDTH="53%"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>C. RICHARD REESE</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Name:&nbsp;C. Richard Reese<BR>
Title:&nbsp;&nbsp;&nbsp;Chief Executive Officer and President</FONT></TD>
</TR>
</TABLE>
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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant
to the requirements of the Securities Act of 1933, this registration statement on Form&nbsp;S-8 has been signed below by the following persons in the capacities
and on the dates indicated. The undersigned officers and directors of the Company hereby severally constitute and appoint C. Richard Reese and John F. Kenny, Jr., and each of them acting singly, our
true and lawful attorneys to sign for us and in our names in the capacities indicated below any and all amendments or supplements, whether pre-effective or post-effective, to
this registration statement on Form&nbsp;S-8 and to file the same, with exhibits thereto and other documents in connection therewith, with the Commission, granting unto each of said
attorneys, acting singly, full power and authority to do and perform each and every act and thing requisite or necessary to be done in and about the premises, as fully to all intents and purposes as
he or she might or could do in person, hereby ratifying and confirming our signatures to said amendments to this registration statement signed by our said attorneys and all else that said attorneys
may lawfully do and cause to be done by virtue hereof. </FONT></P>

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<TH WIDTH="38%" ALIGN="CENTER"><FONT SIZE=1><B>Signature</B></FONT><HR NOSHADE></TH>
<TH WIDTH="2%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="40%" ALIGN="CENTER"><FONT SIZE=1><B>Title</B></FONT><HR NOSHADE></TH>
<TH WIDTH="2%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="18%" ALIGN="CENTER"><FONT SIZE=1><B>Date</B></FONT><HR NOSHADE></TH>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><BR><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" VALIGN="CENTER"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2>/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>C. RICHARD REESE </FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> C. Richard Reese</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2>Chairman, Chief Executive Officer, President and Director</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2>April 12, 2004</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>JOHN F. KENNY, JR.</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> John F. Kenny, Jr.</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Executive Vice President, Chief Financial Officer and Director</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
April 12, 2004</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>CLARKE H. BAILEY</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Clarke H. Bailey</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
April 12, 2004</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>CONSTANTIN R. BODEN</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Constantin R. Boden</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
April 12, 2004</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>KENT P. DAUTEN</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Kent P. Dauten</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
April 12, 2004</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>EUGENE B. DOGGETT</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Eugene B. Doggett</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
April 12, 2004</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="18%" VALIGN="CENTER"><FONT SIZE=2>&nbsp;</FONT></TD>
</TR>
</TABLE>

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/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>B. THOMAS GOLISANO</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Thomas Golisano</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
April 12, 2004</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>ARTHUR D. LITTLE</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Arthur D. Little</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
April 12, 2004</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>VINCENT J. RYAN</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Vincent J. Ryan</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
April 12, 2004</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="38%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>JEAN A. BUA</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Jean A. Bua</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Vice President and Corporate Controller</FONT></TD>
<TD WIDTH="2%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="18%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
April 12, 2004</FONT></TD>
</TR>
</TABLE>
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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to the requirements of the Securities Act of 1933, the Retirement Plan Committee, as administrator of the Plan, has duly caused this Registration
Statement on Form&nbsp;S-8 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Boston, Commonwealth of Massachusetts, on the 12th day of April, 2004. </FONT></P>

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<TD COLSPAN=4><FONT SIZE=2><B>THE IRON MOUNTAIN COMPANIES 401(k) PLAN</B></FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><B><BR>
&nbsp;</B></FONT></TD>
<TD WIDTH="5%"><FONT SIZE=2><B><BR>
&nbsp;</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD COLSPAN=2><FONT SIZE=2><B><BR>
Retirement Plan Committee</B></FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><B><BR>
&nbsp;</B></FONT></TD>
<TD WIDTH="5%"><FONT SIZE=2><B><BR>
&nbsp;</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%"><BR><FONT SIZE=2>By:</FONT></TD>
<TD WIDTH="48%"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>PATRICIA M. BOWLER</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Name: Patricia M. Bowler</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="5%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="5%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="48%"><FONT SIZE=2>&nbsp;</FONT></TD>
</TR>
</TABLE>
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<BR>
<P><br><A NAME="04BOS1472_1">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_ca1472_1">PART I&#151;INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS</A></FONT><BR>
<UL>
<FONT SIZE=2><A HREF="#toc_ca1472_2">Item 1. Plan Information; Item 2. Registrant Information and Employee Plan Annual Information.</A></FONT><BR>
</UL>
<FONT SIZE=2><A HREF="#toc_ca1472_3">PART II&#151;INFORMATION REQUIRED IN THE REGISTRATION STATEMENT</A></FONT><BR>
<UL>
<FONT SIZE=2><A HREF="#toc_ca1472_4">Item 3. Incorporation of Documents by Reference.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_ca1472_5">Item 4. Description of Securities.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_ca1472_6">Item 5. Interests of Named Experts and Counsel.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_ca1472_7">Item 6. Indemnification of Directors and Officers.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_ca1472_8">Item 7. Exemption from Registration Claimed.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_ca1472_9">Item 8. Exhibits.</A></FONT><BR>
</UL>
<FONT SIZE=2><A HREF="#toc_ca1472_10">EXHIBIT INDEX</A></FONT><BR>
<UL>
<FONT SIZE=2><A HREF="#toc_ca1472_11">Item 9. Undertakings.</A></FONT><BR>
</UL>
<!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_jc1472_1">SIGNATURES</A></FONT><BR>
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</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>3
<FILENAME>a2133163zex-5_1.htm
<DESCRIPTION>EXHIBIT 5.1
<TEXT>
<HTML>
<HEAD>

</HEAD>
<BODY BGCOLOR="#FFFFFF" LINK=BLUE  VLINK=PURPLE>
<BR>
<P ALIGN="RIGHT"><FONT SIZE=2><B>Exhibit 5.1  </B></FONT></P>

<UL>
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<UL>
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<UL>

<P><FONT SIZE=2>April
12, 2004 </FONT></P>

</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>

<P><FONT SIZE=2>Iron
Mountain Incorporated<BR>
745 Atlantic Avenue<BR>
Boston, Massachusetts 02111 </FONT></P>

<P><FONT SIZE=2>Ladies
and Gentlemen: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In
connection with the registration under the Securities Act of 1933, as amended (the "Act"), by Iron Mountain Incorporated, a Pennsylvania corporation (the "Company"), of 500,000 shares
of its Common Stock, par value $.01 per share (the "Registered Shares"), that are to be offered and may be issued under The Iron Mountain Companies 401(k) Plan (the "Plan"), the following opinion is
furnished to you to be filed with the Securities and Exchange Commission (the "Commission") as Exhibit&nbsp;5.1 to the Company's registration statement on Form&nbsp;S-8 (the
"Registration Statement") under the Act. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We
have acted as counsel to the Company in connection with the Registration Statement, and we have examined originals or copies, certified or otherwise identified to our satisfaction, of
the Registration Statement, the Amended and Restated Articles of Incorporation of the Company as presently in effect, corporate records of the Company, and such other documents as we have considered
necessary in order to furnish the opinion hereinafter set forth. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We
express no opinion herein as to the laws of any jurisdiction other than the Commonwealth of Massachusetts and the federal laws of the United States, and we express no opinion as to
state securities or blue sky laws. Insofar as this opinion involves matters of Pennsylvania law we have, with your permission, relied solely on the opinion of Ballard Spahr Andrews&nbsp;&amp; Ingersoll,
LLP, a copy of which is being filed herewith as Exhibit&nbsp;5.2 to the Registration Statement, and our opinion is subject to the exceptions, qualifications and limitations therein expressed. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Based
on and subject to the foregoing, we are of the opinion that, when issued in accordance with the terms of the Plan, the Registered Shares will be duly authorized, validly issued,
fully paid and nonassessable by the Company. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We
hereby consent to the filing of this opinion as an exhibit to the Registration Statement. In giving such consent, we do not thereby admit that we come within the category of persons
whose consent is required under Section&nbsp;7 of the Act or the rules and regulations of the Commission promulgated thereunder. </FONT></P>

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<TD WIDTH="57%"><FONT SIZE=2>Very truly yours,</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="43%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="57%"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>SULLIVAN &amp; WORCESTER LLP</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
</TR>
</TABLE>
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<DOCUMENT>
<TYPE>EX-5.2
<SEQUENCE>4
<FILENAME>a2133163zex-5_2.htm
<DESCRIPTION>EXHIBIT 5.2
<TEXT>
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<HEAD>

</HEAD>
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<BR>
<P ALIGN="RIGHT"><FONT SIZE=2><B>Exhibit 5.2  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B> Letterhead of Ballard Spahr Andrews &amp; Ingersoll, LLP  </B></FONT></P>

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<UL>

<P><FONT SIZE=2>April&nbsp;12,
2004 </FONT></P>

</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>

<P><FONT SIZE=2>Iron
Mountain Incorporated<BR>
745 Atlantic Avenue<BR>
Boston, MA 02111 </FONT></P>

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<TD WIDTH="9%"><FONT SIZE=2>Re:</FONT></TD>
<TD WIDTH="91%"><FONT SIZE=2>Registration Statement on Form S-8</FONT></TD>
</TR>
</TABLE></DIV>
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<P><FONT SIZE=2>Ladies
and Gentlemen: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We
have acted as Pennsylvania counsel to Iron Mountain Incorporated, a Pennsylvania corporation (the "Company"), in connection with the registration under the Securities Act of 1933, as
amended (the
"Act"), by the Company of 500,000 shares (the "Shares") of its common stock, par value $.01 per share, that are issuable pursuant to the provisions of The Iron Mountain Companies 401(k) Plan (the
"Plan"). The following opinion is furnished to you to be filed with the Securities and Exchange Commission as Exhibit&nbsp;5.2 to the Company's registration statement on Form&nbsp;S-8
under the Act. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In
rendering our opinion, we have examined originals or copies, certified or otherwise identified to our satisfaction, of the Plan and such other documents, certificates and other
instruments and such matters of law as in our judgment are necessary or appropriate to enable us to render the opinion expressed below. In giving this opinion, we are assuming the authenticity of all
instruments presented to us as originals, the conformity with the originals of all instruments presented to us as copies and the genuineness of all signatures. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We
express no opinion herein as to the laws of any jurisdiction other than the Commonwealth of Pennsylvania, and we express no opinion as to securities or blue sky laws. This opinion is
limited to the matters expressly stated herein. No implied opinion may be inferred to extend this opinion beyond the matters expressly stated herein. We do not undertake to advise you or anyone else
of any changes in the opinions expressed herein resulting from changes in law, changes in fact or any other matters that hereafter might occur or be brought to our attention. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Based
on and subject to the foregoing, we are of the opinion that when issued and paid for in accordance with the terms of the Plan, the Shares will be legally issued, fully paid and
non-assessable. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We
consent to the filing of this opinion as an exhibit to the Registration Statement on Form&nbsp;S-8 being filed with respect to the Shares. </FONT></P>

<UL>
<UL>
<UL>
<UL>
<UL>
<UL>
<UL>
<UL>
<UL>
<UL>
<UL>

<P><FONT SIZE=2>Sincerely,
</FONT></P>

<P><FONT SIZE=2>/s/
Ballard Spahr Andrews&nbsp;&amp; Ingersoll, LLP </FONT></P>

</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
</UL>
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<TYPE>EX-23.3
<SEQUENCE>5
<FILENAME>a2133163zex-23_3.htm
<DESCRIPTION>EXHIBIT 23.3
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<P ALIGN="RIGHT"><FONT SIZE=2><B>Exhibit 23.3  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>INDEPENDENT AUDITORS' CONSENT  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We consent to the incorporation by reference in this registration statement of Iron Mountain Incorporated on Form&nbsp;S-8 of our report (which
report expresses an unqualified opinion and includes an explanatory paragraph relating to the application of procedures relating to certain disclosures and reclassifications of financial statement
amounts related to the 2001 financial statements that were audited by other auditors who have ceased operations and the adoption of Statement of Financial Accounting Standard No.&nbsp;142) dated
March&nbsp;8, 2004, relating to the consolidated financial statements of Iron Mountain Incorporated as of and for the years ended December&nbsp;31, 2003 and 2002 appearing in the Annual Report on
Form&nbsp;10-K of Iron Mountain Incorporated for the year ended December&nbsp;31, 2003. </FONT></P>


<P><FONT SIZE=2>/s/
DELOITTE&nbsp;&amp; TOUCHE LLP </FONT></P>

<P><FONT SIZE=2>Boston,
Massachusetts<BR>
April&nbsp;12, 2004 </FONT></P>

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<TYPE>EX-23.4
<SEQUENCE>6
<FILENAME>a2133163zex-23_4.htm
<DESCRIPTION>EXHIBIT 23.4
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<P ALIGN="RIGHT"><FONT SIZE=2><B>Exhibit&nbsp;23.4  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B> INDEPENDENT AUDITORS' CONSENT  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;As independent public accountants, we hereby consent to the incorporation by reference in this registration statement on Form&nbsp;S-8 of our report
dated March&nbsp;8, 2004 (which expresses an unqualified opinion) on Iron Mountain Europe Limited's consolidated financial statements, included in Iron Mountain Incorporated's Annual Report on
Form&nbsp;10-K for the year ended December&nbsp;31, 2003, filed with the Securities and Exchange Commission on March&nbsp;11, 2004 and to all references to our Firm included in this
registration statement. </FONT></P>

<P><FONT SIZE=2>/s/
RSM Robson Rhodes LLP </FONT></P>

<P><FONT SIZE=2>Chartered
Accountants<BR>
Birmingham, England </FONT></P>

<P><FONT SIZE=2>April&nbsp;12,
2004 </FONT></P>

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