Exhibit 10.20

                                                                  CONFORMED COPY
                             STOCKHOLDERS' AGREEMENT


                     AGREEMENT, dated as of February 19, 1997, among Iron
Mountain Incorporated, a Delaware corporation ("Acquiror"), those stockholders
of Safesite Records Management Corporation, a Delaware corporation (the
"Company") signatory hereto (the "Initial Stockholders"), including, without
limitation, B. Thomas Golisano, an individual residing at 911 Panorama Trail
South, Rochester, NY 14625 ("Golisano"), and James B. Wayman, Jr., an individual
residing at 251 Old Billerica Road, Bedford, MA 01730 ("Wayman"), in his
individual capacity and as custodian for Alexander B. Wayman and Catherine Lia
Wayman and those other stockholders of the Company which have become party
hereto by execution of an instrument in accordance with Section 6.8 hereof (the
"Additional Stockholders" and, together with the Initial Stockholders, the
"Stockholders").

                              W I T N E S S E T H:

                     WHEREAS, each of the Initial Stockholders is the beneficial
and record owner of the shares of Common Stock, $.01 par value per share (the
"Company Stock") of the Company, set forth opposite each such Initial
Stockholder's name on Schedule A-1;

                     WHEREAS, concurrently with the execution of this Agreement,
Acquiror and the Company are entering into an Agreement and Plan of Merger (the
"Merger Agreement") pursuant to which a wholly owned subsidiary of Acquiror will
be merged with and into the Company (the "Merger"), with the Company continuing
as the Surviving Corporation; and

                     WHEREAS, in order to induce Acquiror to enter into the
Merger Agreement, the Stockholders wish to make certain representations,
warranties, covenants and agreements in connection with the Merger.

                     NOW, THEREFORE, in consideration of the premises and other
good and valuable consideration, the receipt and adequacy of which are hereby
acknowledged, the parties hereto hereby agree as follows:


                                    ARTICLE I

                                   DEFINITIONS

                     1.1 Definitions. Capitalized terms used herein but not
otherwise defined herein shall have the respective meanings ascribed thereto in
the Merger Agreement and the following terms shall have the following meanings:

                     "Additional Stockholders" shall have the meaning set forth
in the opening paragraph of this Agreement.



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                     "beneficially own" shall have the meaning set forth in Rule
13d-3 under the Exchange Act.

                     "Equity Securities" shall have the meaning set forth in
Rule 405 under the Securities Act.

                     "Golisano" shall have the meaning set forth in the opening
paragraph of this Agreement.

                     "Initial Stockholders" shall have the meaning set forth in
the opening paragraph of this Agreement.

                     "Intention" shall have the meaning set forth in Section
2.1(f).

                     "Merger Agreement" shall have the meaning set forth in the
second recital of this Agreement.

                     "Offer" and "Offer Consideration" shall have the meanings
set forth in Section 3.7(a).

                     "Permitted Assignee" shall mean with respect to each
Stockholder, (x) such Stockholder's lineal descendants, siblings and lineal
descendants of siblings, (y) a trust for the benefit of, the estate of,
executors, personal representatives, administrators, guardians or conservators
of, any of the individuals referred to in the foregoing clause (x) (but only in
their capacity as such) and (z) charitable trusts and charitable foundations
formed by such Stockholder.

                     "Proportionate Share" shall mean, as to each Stockholder, a
fraction the numerator of which is the Offer Consideration such Stockholder
receives pursuant to the Offer and the denominator of which is the Offer
Consideration all Stockholders receive pursuant to the Offer.

                     "Related Transaction" shall mean a transaction that is in
contemplation of, or related or pursuant to, the Merger or the Merger Agreement.

                     "Restricted Stockholder" shall mean any Stockholder that,
individually or together with its Affiliates, beneficially owns, or is a member
of a "group" (within the meaning of Section 13(d)(3) of the Exchange Act) that
beneficially owns, 5% or more of Acquiror Stock.

                     "Sale" shall have the meaning set forth in Section 2.1(f).

                     "Stockholder Disclosure Letter" shall have the meaning set
forth in Section 2.1(a).

                     "Third Party" shall mean a party or parties unaffiliated
with either the Company or Acquiror.

                     "Transfer" shall have the meaning set forth in Section 3.8.

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                     "Voting Securities" shall have the meaning set forth in
Rule 405 under the Securities Act.

                     "Wayman" shall have the meaning set forth in the opening
paragraph of this Agreement.

                                   ARTICLE II

                         REPRESENTATIONS AND WARRANTIES
                               OF THE STOCKHOLDERS

                     2.1 Representations and Warranties of the Stockholders.
Each Stockholder represents and warrants, severally but not jointly, to Acquiror
as follows:

                     (a) Ownership of Company Shares. Except as disclosed in
Section 2.1(a) of the letter from the Stockholders to Acquiror, dated the date
hereof or the date such Stockholder becomes party hereto (the "Stockholder
Disclosure Letter"), such Stockholder is the beneficial owner of the shares of
Company Stock set forth opposite such Stockholder's name on Schedule A-1, free
and clear of all Liens and, except for this Agreement and the Merger Agreement,
there are no options, warrants or other rights, agreements, arrangements or
commitments of any character to which such Stockholder is a party relating to
the pledge, disposition or voting of any shares of the Company Stock that are
owned by such Stockholder, and there are no voting trusts or voting agreements
with respect to such shares. The shares of Company Stock set forth opposite such
Stockholder's name on Schedule A-1 constitute all of the outstanding shares of
capital stock of the Company owned beneficially or of record by such Stockholder
and such Stockholder does not have any options, warrants or other rights to
acquire any additional shares of capital stock of the Company or any security
exercisable or exchangeable for, or convertible into, shares of capital stock of
the Company other than as set forth on Schedule A-1.

                     (b) Authority to Execute and Perform Agreements. Such
Stockholder has the full legal right and power and all authority required to
enter into, execute and deliver this Agreement and to perform fully such
Stockholder's obligations hereunder. The execution and delivery of this
Agreement by such Stockholder have been duly authorized by all requisite
organizational action, if any, on the part of such Stockholder. This Agreement
has been duly executed and delivered and constitutes the legal, valid and
binding obligation of such Stockholder enforceable against such Stockholder in
accordance with its terms (subject to the Enforceability Exceptions).

                     (c) No Conflicts; Consents. (i) Except as set forth in
Section 2.1(c) of the Stockholder Disclosure Letter, the execution and delivery
by such Stockholder of this Agreement do not, and the consummation of the
transactions contemplated hereby will not, conflict with or result in any
violation of or default (with or without notice or lapse of time, or both) under
(A) any contract, agreement or other binding arrangement to which such
Stockholder is a party or (B)

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any judgment, order, writ, injunction or decree of any court, governmental body,
administrative agency or arbitrator applicable to such Stockholder.

                     (ii) Except as set forth in Section 2.1(c) of the
Stockholder Disclosure Letter, no Governmental Authorizations or Private
Authorizations are required to be obtained or made by such Stockholder in
connection with the execution and delivery by such Stockholder of this Agreement
and the consummation of the transactions contemplated hereby.

                     (d) Information Supplied. None of the information
specifically supplied or to be supplied by such Stockholder with respect to such
Stockholder for inclusion or incorporation by reference in (i) the Registration
Statement will, at the time the Registration Statement is filed with the SEC and
at the time it becomes effective under the Securities Act, contain any untrue
statement of a material fact or omit to state any material fact required to be
stated thereon or necessary to make the statements therein not misleading and
(ii) the proxy statement to be delivered to all stockholders of the Company (the
"Proxy Statement") will, at the date the Proxy Statement is first mailed to the
Company's Stockholders and at the time of the special meeting of Company
Stockholders for the purpose of voting on the Merger Agreement, contain any
untrue statement of a material fact or omit to state any material fact required
to be stated therein or necessary in order to make the statements therein, in
light of the circumstances under which they are made, not misleading.

                     (e) Investigation. Such Stockholder has had a full
opportunity to review and discuss this Agreement, the Escrow Agreement and the
Merger Agreement (including, without limitation, with respect to the
representations and warranties in the Merger Agreement and the related
Disclosure Schedule) and to ask all questions of the Company and its directors
and executive officers necessary in order for such Stockholder to make an
informed decision to enter into this Agreement.

                     (f) Intent to Transfer Shares. Such Stockholder has, and as
of the Closing Date, will have, no present plan or intention (an "Intention") to
sell, transfer, exchange, pledge (other than in a pre-existing bona fide margin
account) or otherwise dispose of, including a distribution by a partnership to
its partners, or a corporation to its shareholders, or any other transaction
which results in a reduction of ownership (any of the foregoing, a "Sale") of
any of the shares of Acquiror Stock issued to such Stockholder in the Merger, or
any securities that may be paid as a dividend otherwise distributed thereon or
with respect thereto, or issued or delivered in exchange or substitution
therefor or upon exercise of options held by such Stockholder. For purposes of
the preceding sentence, shares of Acquiror Stock (or the portion thereof) with
respect to which a Sale will occur prior to the Merger shall be considered to be
shares of Company Stock that are exchanged for Acquiror Stock in the Merger and
then disposed of pursuant to an Intention. A Sale of Acquiror Stock shall be
considered to have occurred pursuant to an Intention if, among other things,
such Sale occurs in a related transaction. Subject to Section 3.8, each
Stockholder (i) reserves the rights at any time after the Closing Date to
evaluate his or her investment portfolio, including shares of Acquiror Stock and
any other securities issued by Acquiror, in light of new, material developments,
and to make such investment decision with respect to such securities as

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such Stockholder and his or her investment advisors, if any, shall deem to be in
his or her best interests, and (ii) specifically disavows any undertaking to
hold any securities issued by Acquiror for any specific period.

                                   ARTICLE III

                                    COVENANTS

                     3.1 No Disposition or Acquisition of Shares. Each Initial
Stockholder agrees that, except as set forth in Section 3.1 of the Stockholder
Disclosure Letter, such Initial Stockholder shall not sell, transfer, pledge,
hypothecate, encumber or otherwise dispose of (except upon such Stockholder's
death), or enter into any contract, option or other arrangement or understanding
with respect to the sale, transfer, pledge, hypothecation, encumbrance or other
disposition of, any of the shares of Company Stock set forth opposite his or her
name on Schedule A-1; provided, however, that each Initial Stockholder shall
have the right to transfer such shares to a Permitted Assignee if such Permitted
Assignee becomes a party to this Agreement and agrees to be bound by the terms
hereof. Each Initial Stockholder agrees that the certificates representing the
shares of Company Stock owned by him shall bear a legend indicating that such
shares are subject to this Agreement, which legend may be removed upon
termination of this Agreement.

                     3.2 Voting Arrangements. Each of Golisano and Wayman agrees
that, except pursuant to this Agreement, he shall not grant any proxies, deposit
any shares of Company Stock into a voting trust or enter into any voting
agreement with respect to any shares of Company Stock now or hereafter owned,
beneficially or of record, by him, other than proxies to vote such shares at any
annual or special meeting of Stockholders of the Company on matters unrelated to
the matters set forth in Section 4.1 hereof.

                     3.3 Satisfaction of Conditions to the Merger. Each of
Golisano and Wayman agrees that each, in his capacity as a Stockholder, shall
assist and cooperate with the parties to the Merger Agreement in doing all
things necessary, proper or advisable under Applicable Laws as promptly as
practicable to consummate and make effective the Merger and the other
Transactions and each of them shall not take any action that would or is
reasonably likely to result in any of its representations and warranties set
forth in this Agreement being untrue as of the date made or in any of the
conditions set forth in Article 6 of the Merger Agreement not being satisfied.
In addition, (i) Acquiror, Golisano and Wayman agree that they will enter into,
or, in the case of Acquiror, cause its nominee to enter into, and, in the case
of Golisano and Wayman, cause their Affiliate which owns any Property to enter
into, a purchase and sale agreement relating to each Property reasonably
satisfactory in form and substance to Acquiror, Golisano and Wayman, for the
price of $2,200,000 for the Property located at 5 Fortune Drive, Billerica,
Massachusetts, $2,400,000 for the Property located at 96 High Street, Billerica,
Massachusetts, and $2,700,000 for the Property located at 520 Metro Park West,
Rochester, New York, and (ii) Acquiror, Golisano and Wayman agree that they will
enter into the Registration Rights Agreement.


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                     3.4 No Solicitation. Each Stockholder agrees that he shall
not, nor shall he permit any of such Stockholder's Representatives (including,
without limitation, any investment banker, attorney or accountant retained by
such Stockholder) to, initiate, solicit or facilitate, directly or indirectly,
any inquiries or the making of any proposal with respect to an Other
Transaction, engage in any discussions or negotiations concerning, or provide to
any other person any information or data relating to, such Stockholder for the
purposes of, or otherwise cooperate in any way with or assist or participate in,
or facilitate any inquiries or the making of any proposal which constitutes, or
may reasonably be expected to lead to, a proposal to seek or effect an Other
Transaction, or agree to or endorse any Other Transaction; provided, however,
that nothing contained in this Section shall prohibit any Stockholder, if such
Stockholder is a member of Board of Directors of the Company, from making any
disclosure, in his or her capacity as a director of the Company, to other
Stockholders of the Company that, in the reasonable judgment of the Company's
Board of Directors in accordance with, and based upon the written advice of,
outside counsel, is required under Applicable Law. Each Stockholder shall
promptly advise Acquiror of, and communicate the material terms of, any proposal
such Stockholder may receive, or any inquiries such Stockholder receives which
may reasonably be expected to lead to such a proposal relating to an Other
Transaction, and the identity of the Person making it. Each Stockholder shall
further advise Acquiror of the status and changes in the material terms of any
such proposal or inquiry (or any amendment to any of them). During the term of
this Agreement, each Stockholder agrees that he shall not enter into any
agreement oral or written, and whether or not legally binding, with any Person
that provides for, or in any way facilitates, an Other Transaction, or affects
any other obligation of the other Stockholders under this Agreement.

                     3.5 Standstill. Golisano agrees that, (i) from the date
hereof until the Closing Date and (ii) from and after the Closing Date for so
long as he shall be a Restricted Stockholder, he shall not, and shall use his
best efforts to cause his Affiliates not to, without the prior written consent
of the board of directors of Acquiror, (A) in any manner acquire, agree to
acquire or make any proposal to acquire, directly or indirectly, any Equity
Securities of Acquiror or any rights or options to acquire such Equity
Securities (other than the shares of Acquiror Stock received by him in the
Merger), (B) propose to enter into, directly or indirectly, a merger or other
business combination involving Acquiror or propose to purchase, directly or
indirectly, a material portion of the assets of Acquiror, (C) make, or in any
way participate, directly or indirectly, in, any "solicitation" of "proxies" (as
such terms are used in Regulation 14A under the Exchange Act) to vote or consent
or seek to advise or influence any Person with respect to the voting of, or
granting of a consent with respect to, any Voting Securities of Acquiror, (D)
form, join or in any way participate in a "group" (within the meaning of Section
13(d)(3) of the Exchange Act) for the purpose of acquiring, holding voting or
disposing of any Equity Securities of Acquiror, (E) otherwise act, alone or in
concert with others, to seek to control or influence in any public manner or
public forum the management or policies of Acquiror; provided, however, that the
foregoing shall not limit the ability to vote any shares of any Equity
Securities of Acquiror, (F) disclose any intention, plan or arrangement
inconsistent with the foregoing, (G) advise, assist (including by knowingly
providing or arranging financing for that purpose) or encourage any other Person
in connection with any of the foregoing or (H) take any action which might
require Acquiror to make

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a public announcement regarding the possibility of a transaction between
Golisano and Acquiror (including any of their respective Affiliates).

                     3.6 Non-Competition.

                     (a) Except with the prior written consent of Acquiror, for
a period of five years from the Closing Date or the date of the closing of the
Offer, each of Golisano and Wayman shall not disclose to others or use for his
or others' benefit confidential information related to the Company or Acquiror
and its Subsidiaries, including the names of customers, the contact persons at
customers, pricing, the software programs utilized by the Company or Acquiror
and its Subsidiaries in the operation of its business and all other information
material to the operation, management, marketing or financing of the Company,
Acquiror and its Subsidiaries which is not known or generally available to the
public or competitors in the records management or records storage industries.

The confidentiality obligations of this Section shall not apply to information:

                     (i) which is required to be disclosed by judicial or
administrative process or order, or by other requirements of law;

                     (ii) which is or becomes generally available to the public
other than as a result of a breach of this Section;

                     (iii) which is received from a third party who obtained
such information other than under an obligation of confidentiality; or

                     (iv) which Acquiror discloses on a nonconfidential basis or
otherwise makes available to the general public or the trade.

                     (b) Each of the Golisano and Wayman agrees that he shall
not, for a period of five years from the Closing Date or from the date of the
closing of the Offer, directly or indirectly own, manage, engage in, participate
in, provide advice to, be employed by or have a financial interest in, any
enterprise which provides records management or records storage services to
business facilities located in any jurisdiction in which Acquiror or the Company
operates.

           This Section 3.6(b) shall not prohibit either Golisano or Wayman from
acquiring up to five percent (5%) of any class of securities registered pursuant
to the Exchange Act of any corporation which may engage in the records
management storage service business in direct competition with the business of
Acquiror within the geographical areas set forth in this Section 3.6.

                     (c) Each of Golisano and Wayman acknowledges that it has
carefully read all the terms herein stated and agrees that the same are
necessary for the reasonable and proper protection of the value of the Company;
and that each and every covenant is reasonable with respect to such matter,
length of time, and the geographical areas described; and that irrespective

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of all other conditions, the covenants and restrictions hereinabove provided
shall be operative during the full period and throughout the geographical area
described. In the event any court finds any such restraint or limitation to be
unreasonable, then it is the intent of the parties that such court should
determine the maximum restraint or limitation which is reasonable and
enforcement will be of that restraint or limitation.

                     (d) Each of Golisano and Wayman acknowledges that
confidential information in his possession related to the Company has particular
value, the loss of confidentiality of which by communication to unauthorized
persons cannot be reasonably or adequately compensated for by damages alone.
Moreover, each of Golisano and Wayman agrees that any breach of paragraphs (a)
and (b) of this Section 3.6 would give rise to damages which would be difficult
to calculate. Therefore, the parties hereby agree that in the event of a breach
of any of the terms and conditions of this Section 3.6, Acquiror shall be
entitled to equitable relief by way of an injunction. This Section 3.6 shall not
be construed as a limitation upon Acquiror's remedies for such breach.

                     (e) The restrictions contained in this Section 3.6 shall be
broadly construed by any court having jurisdiction of the matter in order to
protect Acquiror to the maximum degree possible.

                     3.7 Tender Offer; Commitment to Sell.

                     (a) If Acquiror terminates the Merger Agreement pursuant to
Section 7.1(d) thereof (other than a termination by Acquiror pursuant to Section
7.1(d)(ii)(B)(II) unless the reason for the failure to consummate the Merger
prior to the Termination Date is due to any breach by the Company of its
covenants therein or the failure of the representations and warranties of the
Company to be true and correct in all material respects), it shall have the
right, but not the obligation, to commence an offer (the "Offer") to purchase
all of the outstanding Shares at a per share purchase price (the "Offer
Consideration") equal to the Merger Consideration (assuming for such purposes
that the commencement of the Offer would constitute a Change of Control under
the Option Plans and, as a consequence thereof, there would be an acceleration
of the Option Securities as of the date of commencement of the Offer, as set
forth in Section 3.13(b) of the Disclosure Schedule). Shares tendered in the
Offer shall be free and clear of all Liens. The Offer shall comply in all
material respects with Applicable Law.

                     (b) Each of Golisano and Wayman hereby agrees that they
will irrevocably tender their shares of Company Stock identified on Schedule A-1
hereto in any such Offer commenced by Acquiror and, in connection therewith,
transfer to Acquiror all of the right, title and interest of each of Golisano
and Wayman in and to such shares, free and clear of all Liens.

                     (c) All of the representations, warranties and covenants
made by the Company in the Merger Agreement shall be deemed made in connection
with the Offer by each Stockholder who tenders shares in the Offer, which
representations, warranties and covenants shall survive for a period of one year
after the closing of the Offer. Any claim for indemnification in respect of
breaches of such representations, warranties and covenants shall be conducted in
accordance with

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the provisions of Article 8 of the Merger Agreement and Article 5 of this
Agreement (except that there will be no Escrow Indemnity Fund).

                     (d) The closing of the Offer shall take place in accordance
with the instructions set forth in the Offer. At such closing, (A) Acquiror
shall make payment of the Offer Consideration to each Stockholder who tenders
their shares in the Offer in shares of Acquiror Stock, which shares shall be
duly authorized, validly issued, fully paid and nonassessable, and the cash
portion of the Exchange Merger Consideration and cash in lieu of fractional
shares, (B) each of Golisano and Wayman shall deliver to Buyer evidence
reasonably satisfactory to Buyer and its counsel that all necessary
authorizations, consents, orders, waivers and approvals have been obtained to
vest in Buyer all of the right, title and interest of the Shares being
transferred to Buyer by them, and (C) each Stockholder who tenders Shares in the
Offer shall deliver to Acquiror the Certificates representing such Shares duly
endorsed for transfer to Acquiror or with stock powers duly executed by such
Stockholder and otherwise in a form and at the time which complies with the
terms of the Offer.

                     (e) It is the understanding of Acquiror, and each of
Golisano and Wayman hereby represents, that, in the event of an acquisition of
shares of Acquiror Stock in the Offer, each of Golisano and/or Wayman will be
acquiring the shares of Acquiror Stock to be acquired by him through the Offer
for his own account for investment with no intention of presently distributing
or reselling the same, subject, nevertheless, to his right to dispose of such
Shares, or any part of any thereof held by him, if at some future time in his
sole discretion he deems it advisable so to do. Each of Golisano and Wayman
hereby agrees that he will not sell, transfer or otherwise dispose of any such
shares of Acquiror Stock in violation of the Securities Act, and that such
shares of Acquiror Stock may contain a legend, reasonably satisfactory to
Acquiror, referring to the provisions of this Section. Each of Golisano and
Wayman understands that the Company is not and will not be required to file a
registration statement under the Securities Act in connection with any sale,
transfer or other disposition of shares of Acquiror Stock which may be acquired
by either Golisano or Wayman pursuant to the Offer.

                     (f) The undertakings in this Section 3.7 shall terminate
upon the earlier of (i) the Effective Time, (ii) the termination of the Merger
Agreement in accordance with Section 7.1 thereof (other than a termination which
results in Acquiror having the right to make the Offer in accordance with this
Section 3.7) or (iii) six months after a termination which results in Acquiror
having the right to make the Offer in accordance with this Section 3.7 (provided
that on or before thirty days after such termination Acquiror shall have
provided notice to Golisano of its intention to commence the Offer).

                     3.8 Post-Closing Transfer Restrictions. In the event the
Merger is consummated as an Alternative Transaction, each of the Stockholders
agrees that, from and after the Closing Date until the one-year anniversary
thereof, such Stockholder shall not sell, transfer, pledge, encumber or
otherwise dispose of, including through any "short sale" or derivative
transactions (collectively "Transfer"), any shares of Acquiror 


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Stock received by such Stockholder as a result of the Merger if, after giving
effect to such Transfer, the aggregate number of shares of Acquiror Stock
received in the Merger by all Stockholders and not Transferred would be less
than a number of shares of Acquiror Stock having a value, as of the date of the
Merger, of less than fifty percent (50%) of the value of all of the formerly
outstanding Company Stock as of the same date. For purposes of the preceding
computation, shares of Company Stock surrendered by dissenters or exchanged for
cash in lieu of fractional shares of Acquiror Stock will be treated as
outstanding Company Stock on the date of the Merger that has subsequently been
Transferred, and all shares of Company Stock and all shares of Acquiror Stock
held by the Stockholders and Transferred prior or subsequent to the Merger will
be included in the computation.

                     3.9 [Intentionally Omitted.]








                                   ARTICLE IV

                               PROXY; CONVERSION;
                           ELECTIONS; WAIVER OF RIGHTS

                     4.1 Proxy. Each of Golisano and Wayman hereby agrees that,
at any meeting of the stockholders of the Company, however called, and at every
adjournment thereof, and in any action by written consent of the stockholders of
the Company, to (a) vote all of the shares of Company Stock then owned,
beneficially or of record, by him in favor of the adoption of the Merger
Agreement as in effect on the date hereof (as such agreement may be amended (1)
as contemplated by Section 7.3 of the Merger Agreement or (2) with the consent
of such Stockholder) and each of the other transactions contemplated thereby and
any action required in furtherance thereof, (b) vote such shares against any
action or agreement that would result in a breach in any material respect of any
covenant, representation or warranty or any other obligation of the Company
under the Merger Agreement, and (c) vote such shares against any Other
Transaction or any other action or agreement that, directly or indirectly, is
inconsistent with or that would, or is reasonably likely to, directly or
indirectly, impede, interfere with or attempt to discourage the Merger or any
other transaction contemplated by the Merger Agreement, including, but not
limited to (i) any extraordinary corporate transaction (other than the Merger on
the terms set forth in the Merger Agreement), such as a merger, consolidation,
business combination, reorganization recapitalization or liquidation involving
the Company, (ii) a sale or transfer of a material amount of assets of the
Company, or (iii) any material change in the Company's corporate structure or
business; provided, however, that, if either Golisano or Wayman is a member of
the Board of Directors of the Company, nothing herein shall be construed to
obligate such Stockholder or representative to act in his capacity as a director
in any manner which may conflict with such Person's fiduciary duties as a
director of the Company.

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                     In furtherance of the foregoing, (i) each of Golisano and
Wayman hereby appoints Acquiror and the proper officers of Acquiror, and each of
them, with full power of substitution in the premises, its proxies to vote all
his shares of Company Capital Stock at any meeting, general or special, of the
Stockholders of the Company, and to execute one or more written consents or
other instruments from time to time in order to take such action without the
necessity of a meeting of the Stockholders of the Company, in accordance with
the provisions of the preceding paragraph and (ii) Acquiror hereby agrees to
vote such shares or execute written consents or other instruments in accordance
with the provisions of the preceding paragraph.

                     The proxy and power of attorney granted herein shall be
irrevocable during the term of this Agreement, shall be deemed to be coupled
with an interest and shall revoke all prior proxies granted by such Golisano and
Wayman. Each of Golisano and Wayman shall not grant any proxy to any person
which conflicts with the proxy granted herein, and any attempt to do so shall be
void. The power of attorney granted herein is a durable power of attorney and
shall survive the disability or incompetence of such Stockholder.

                     4.2 Appraisal Rights. Each of Golisano and Wayman hereby
waives his rights to appraisal under Section 262 of the DGCL with respect to any
shares of Company Stock owned by him in connection with the transactions
contemplated by the Merger Agreement. Each of Golisano and Wayman hereby agrees
that he will not in any way attempt to influence, encourage or persuade any
Person who beneficially owns any Company Stock to exercise any rights to
appraisal such Person may have pursuant to Section 262 of the DGCL in connection
with said transactions.

                     4.3 Waiver of Certain Rights. Each Initial Stockholder
hereby waives and agrees not to assert any claims or rights it may have against
any officer or director of the Company relating to or arising out of actions or
omissions occurring at or prior to the Effective Time or the closing of the
Offer, as the case may be, including, without limitation, in respect of approval
or adoption of the Merger Agreement or the consummation of the Merger or the
other transactions contemplated thereby.


                                    ARTICLE V

                                 INDEMNIFICATION

                     5.1 Indemnification in the Event of the Offer. Each
Stockholder agrees that the indemnification provisions set forth in Article 8 of
the Merger Agreement shall be applicable in the event Acquiror consummates the
Offer pursuant to Section 3.7 hereof; provided, however, that only Stockholders
who tender Shares in the Offer shall be responsible for such indemnification and




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<PAGE>



each such Stockholder shall only be responsible for such Stockholder's
Proportionate Share of any claim. In addition, (i) the Escrow Indemnity Period
shall terminate on the first anniversary of the closing of the Offer and the
Closing Date shall be deemed to be the closing of the Offer, (ii) the amount of
Acquiror Stock received by each Stockholder who tenders Shares in the Offer
shall be adjusted to reflect the escrow to be established, and (iii) each
Stockholder will agree to execute the Escrow Agreement with such changes
therein, if any, as are necessary to reflect the differences between the Merger
and the Offer.

                     5.2 Exclusive Remedy. Except as otherwise provided in
Article 8 and Section 9.8 of the Merger Agreement, the indemnification provided
in this Article shall be the sole and exclusive post-Closing remedy available to
Acquiror against the Stockholders for any Claim under this Agreement.


                                   ARTICLE VI

                                  MISCELLANEOUS

                     6.1 Termination. This Agreement shall terminate upon the
earlier to occur of (i) the mutual consent of Acquiror and all of the
Stockholders, (ii) one year after the termination of the Merger Agreement prior
to the consummation of the Merger and (iii) the tenth anniversary of the Closing
Date.

                     6.2 Amendment. This Agreement may be amended only by a
written instrument executed by the parties or their respective successors or
assigns.

                     6.3 Notices. Notices, requests, permissions, waivers and
other communications hereunder shall be in writing and shall be deemed to have
been duly given if signed by the respective persons giving them (in the case of
any corporation the signature shall be by an officer thereof) and delivered by
hand, deposited in the United States mail (registered or certified, return
receipt requested), properly addressed and postage prepaid, or delivered by
telecopy:

                     If to Acquiror, to:

                     Iron Mountain Incorporated
                     745 Atlantic Avenue, 10th Floor
                     Boston, Massachusetts 02111
                     Telephone:           (617) 357-4455
                     Telecopy:            (617) 350-7881
                     Attention:           Chairman of the Board


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<PAGE>


                     with a copy to:

                     Sullivan & Worcester LLP
                     One Post Office Square
                     Boston, Massachusetts 02109
                     Telephone:           (617) 338-2800
                     Telecopy:            (617) 338-2880
                     Attention:           William J. Curry, Esq.

                     If to the Stockholders, to:

                     c/o B. Thomas Golisano
                     911 Panorama Trail South
                     Rochester, NY 14625
                     Telephone:           (716) 385-6666
                     Telecopy:            (716) 383-3428

                     with a copy to:

                     Woods, Oviatt, Gilman, Sturman & Clarke LLP
                     44 Exchange Street
                     Rochester, NY 14614
                     Telephone:  (716) 987-2821
                     Telecopy:   (716) 454-3968
                     Attention:  Harry P. Messina, Jr., Esq.

                     6.4 Counterparts. This Agreement may be executed in one or
more counterparts and each counterpart shall be deemed to be an original, but
all of which shall constitute one and the same original.

                     6.5 Applicable Law. This Agreement shall be governed by,
and construed in accordance with the laws of the State of Delaware without
reference to choice of law principles, including all matters of construction,
validity and performance.

                     6.6 Severability; Enforcement. The invalidity of any
portion hereof shall not affect the validity, force or effect of the remaining
portions hereof. If it is ever held that any restriction hereunder is too broad
to permit enforcement of such restriction to its fullest extent, each party
agrees that a court of competent jurisdiction may enforce such restriction to
the maximum extent permitted by law, and each party hereby consents and agrees
that such scope may be judicially modified accordingly in any proceeding brought
to enforce such restriction. In furtherance of the foregoing, if any court
construes any of the provisions of Section 3.6, or any part thereof, to be
unreasonable because of the duration of such provision or the geographic scope
thereof, such court shall have the power to reduce the duration or restrict the
geographic scope of such provision and to enforce such provision as so reduced
or restricted.

                                      -13-

<PAGE>


                     6.7 Further Assurances. Each party hereto shall execute and
deliver such additional documents as may be necessary or desirable to consummate
the transactions contemplated by this Agreement.

                     6.8 Additional Stockholders; Parties in Interest;
Assignment. The parties hereto agree that, from time to time, any and all
Additional Stockholders of the Company may be added as parties hereto by (i)
approving a resolution or taking such other action at the Special Meeting as
Acquiror and the Company may agree upon or (ii) executing a counterpart of this
Agreement or an agreement by which such stockholder agrees to join and to be
bound hereby, and without in either case further action by any party hereto or
thereto. Neither this Agreement nor any of the rights, interest or obligations
hereunder shall be assigned by any of the parties hereto without the prior
written consent of the other parties. Notwithstanding the foregoing, for the
purposes of Sections 3.5 and 3.6, the term Acquiror shall include any Entity
controlling, controlled by or under common control with Acquiror, any successor,
by operation of law or otherwise of Acquiror, or any entity controlling,
controlled by or under common control with Acquiror, and any assignee of
Acquiror.

                     6.9 Entire Agreement. This Agreement and the Merger
Agreement and the Collateral Documents contain the entire understanding of the
parties hereto and thereto with respect to the subject matter contained herein
and therein, and supersede and cancel all prior agreements, negotiations,
correspondence, undertakings and communications of the parties, oral or written,
respecting such subject matter. There are no restrictions, promises,
representations, warranties, agreements or undertakings of any party hereto or
to the Merger Agreement or any of the Collateral Documents with respect to the
transactions contemplated by this Agreement and the Merger Agreement and the
Collateral Documents other than those set forth herein or therein or made
hereunder or thereunder.

                     6.10 Specific Performance. The parties hereto agree that
the remedy at law for any breach of this Agreement will be inadequate and that
any party by whom this Agreement is enforceable shall be entitled to specific
performance in addition to any other appropriate relief or remedy. Such party
may, in its sole discretion, apply to a court of competent jurisdiction for
specific performance or injunctive or such other relief as such court may deem
just and proper in order to enforce this Agreement or prevent any violation
hereof and, to the extent permitted by applicable law, each party waives any
objection to the imposition of such relief.

                     6.11 Headings; References. The section and paragraph
headings contained in this Agreement are for reference purposes only and shall
not affect in any way the meaning or interpretation of this Agreement. All
references herein to "Sections" or "Exhibits" shall be deemed to be references
to Articles or Sections hereof or Exhibits hereto unless otherwise indicated.


                     [Signatures appear on following page.]


                                      -14-

<PAGE>






                     IN WITNESS WHEREOF, each of the parties hereto had caused
this Agreement to be duly executed and delivered as of the day and year first
above written.

                           IRON MOUNTAIN INCORPORATED


                           By: /s/ David S. Wendell
                                   ---------------------------------------------
                                   Name: David S. Wendell
                                   Title: President and Chief Operating Officer


                               /s/ B. Thomas Golisano
                                   ---------------------------------------------
                                   B. Thomas Golisano


                               /s/ James B. Wayman, Jr.
                                   ---------------------------------------------
                                   James B. Wayman, in his individual capacity
                                   and as custodian for Alexander B. Wayman
                                   and Catherine Lia Wayman



                      [Additional signature pages follow.]

                                      -15-

<PAGE>






                                   ---------------------------------------------
                                   Roselee Wayman


                                   ---------------------------------------------
                                   John Glynn


                                  /s/ Harvey H. Bundy III
                                   ---------------------------------------------
                                      Harvey H. Bundy III, in his capacities
                                      as Trustee for each of the Clark H. Bundy
                                      1992 Trust, Elizabeth Lowell Bundy 1996
                                      Trust, H. Hollister Bundy III 1990 Trust
                                      and Harvey H. Bundy III 1992 Trust


                                  /s/ Blakely F. Bundy
                                   ---------------------------------------------
                                      Blakely F. Bundy , in her capacities as
                                      Trustee for the Blakely F. Bundy 1992
                                      Trust and as Custodian for Reed F. Bundy


                                  /s/ David F. Bellet
                                   ---------------------------------------------
                                      David F. Bellet


                                  /s/ Hugh J. Rundle
                                   ---------------------------------------------
                                      Hugh J. Rundle


                                   ---------------------------------------------
                                   Paul R. Altavena


                                  /s/ Charles T. Graham
                                   ---------------------------------------------
                                      Charles T. Graham

                                       -16-