8-K

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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT
                       PURSUANT TO SECTION 13 OR 15(d) OF
                       THE SECURITIES EXCHANGE ACT OF 1934

       Date of Report (Date of earliest event reported): December 7, 2006

                           IRON MOUNTAIN INCORPORATED
             (Exact name of registrant as specified in its charter)

                                    DELAWARE
                 (State or other jurisdiction of incorporation)

           1-13045                                        23-2588479
   (Commission File Number)                    (IRS Employer Identification No.)

                               745 Atlantic Avenue
                           Boston, Massachusetts 02111
          (Address of principal executive offices, including zip code)

                                 (617) 535-4766
              (Registrant's telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2.):

[ ]  Written communications pursuant to Rule 425 under the Securities
     Act (17 CFR 230.425)

[ ]  Soliciting material pursuant to Rule 14a-12 under the Exchange
     Act (17 CFR 240.14a-12)

[ ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[ ]  Pre-commencement communications pursuant to Rule 13e-4(c) under the
     Exchange Act (7 CFR 240.13e-4(c))

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ITEM 8.01.  OTHER EVENTS.

On December 7, 2006, Iron Mountain Incorporated (the "Company") announced the
authorization and approval of a three-for-two stock split effected in the form
of a dividend on the Company's Common Stock, par value $0.01 per share. Shares
of the Common Stock will be issued on December 29, 2006, to all stockholders of
record as of the close of business on December 18, 2006. For more information,
see the Company's press release, dated December 7, 2006, which is filed herewith
as Exhibit 99.1 and is incorporated herein by reference.

ITEM 9.01.  FINANCIAL STATEMENTS AND EXHIBITS.

(d)      Exhibits

99.1     Press Release of Iron Mountain Incorporated dated December 7, 2006
         (filed herewith).



                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                          IRON MOUNTAIN INCORPORATED
                                          (Registrant)


                                          By:    /s/ John F. Kenny, Jr.
                                                 -------------------------------
                                          Name:  John F. Kenny, Jr.
                                          Title: EVP and Chief Financial Officer

Date: December 7, 2006

EX-99.1

                                                                    Exhibit 99.1

          IRON MOUNTAIN INCORPORATED DECLARES THREE-FOR-TWO STOCK SPLIT

    BOSTON, Dec. 7 /PRNewswire-FirstCall/ -- Iron Mountain Incorporated (NYSE:
IRM), the global leader in information protection and storage services, today
announced that the Company's Board of Directors, at a meeting held earlier
today, authorized and approved a three-for-two stock split effected in the form
of a dividend on the Company's Common Stock, par value $.01 per share (the
"Common Stock"). Shares of Common Stock will be issued on December 29, 2006, to
all stockholders of record as of the close of business on December 18, 2006. Any
fractional shares resulting from the dividend will be paid in cash. The stock
split will increase Iron Mountain's total shares outstanding from approximately
133 million to approximately 200 million.

    Richard Reese, Chairman and CEO, stated, "In making its decision to split
the stock, the Board of Directors considered the Company's solid financial
performance together with the continuing appreciation of its stock price. This
action reflects the Board's continued confidence in the long-term performance of
the business. We also believe that the stock split will broaden the
marketability and distribution of our stock."

    About Iron Mountain

    Iron Mountain Incorporated (NYSE: IRM) helps organizations around the world
reduce the costs and risks associated with information protection and storage.
The Company offers comprehensive records management and data protection
solutions, along with the expertise and experience to address complex
information challenges such as rising storage costs, litigation, regulatory
compliance and disaster recovery. Founded in 1951, Iron Mountain is a trusted
partner to more than 90,000 corporate clients throughout North America, Europe,
Latin America and Asia Pacific. For more information, visit the Company's Web
site at http://www.ironmountain.com.

    Investor Relations Contact:
    Stephen P. Golden
    Director, Investor Relations
    sgolden@ironmountain.com
    (617) 535-4799

SOURCE  Iron Mountain Incorporated
    -0-                             12/07/2006
    /CONTACT:  Investor Relations, Stephen P. Golden, Director, Investor
Relations of Iron Mountain Incorporated, +1-617-535-4799, or
sgolden@ironmountain.com/
    /Web site:  http://www.ironmountain.com/