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                                                                    EXHIBIT 99.1

                               ABLECO FINANCE LLC
                                 450 Park Avenue
                               New York, NY 10022

                                                                    May 16, 2001


Outsource International, Inc.
1690 South Congress Avenue
Delray Beach, Florida  33445

Attention:  Chief Financial Officer

                  Re:      DELIVERY OF QUARTERLY FINANCIAL STATEMENTS

Gentlemen:

                  Reference is made to the Financing Agreement, dated as of
August 15, 2000, as amended by the First Amendment dated as of November 8, 2000,
the Second Amendment dated as of November 16, 2000 and the Third Amendment dated
as of April 30, 2001 (as so amended, the "Financing Agreement"), by and among
Outsource International, Inc. (the "Parent"), Outsource International of
America, Inc. ("OIA"), Outsource Franchising, Inc. ("OFI"), Guardian Employer
East, LLC ("Guardian East"), Guardian Employer West, LLC ("Guardian West" and
together with the Parent, OIA, OFI and Guardian East, each a "Borrower" and
collectively, the "Borrowers"), each Subsidiary of the Parent (other than a
Borrower) whose name appears on the signature pages thereof (each a "Guarantor"
and collectively, the "Guarantors"), the financial institutions from time to
time party thereto (each a "Lender" and collectively, the "Lenders"), Ableco
Finance LLC, as collateral agent for the Lenders (in such capacity, the
"Collateral Agent"), and The CIT Group/Business Credit, Inc., as administrative
agent for the Lenders (in such capacity, the "Administrative Agent" and together
with the Collateral Agent, each an "Agent" and collectively, the "Agents"). All
capitalized terms used herein without definitions have the meanings given such
terms in the Financing Agreement.

                  You have advised us that the Administrative Borrower is not
prepared to deliver to the Agents and the Lenders the quarterly financial
statements of the Parent and its Subsidiaries for the fiscal quarter of the
Parent and its Subsidiaries ending April 1, 2001 (the "First Quarter Financial
Statements") as required by Section 7.01(a)(i) of the Financing Agreement. You
have requested that the Required Lenders extend the date by which the
Administrative Borrower must submit the First Quarter Financial Statements from
May 16, 2001 to May 31, 2001.

                  In consideration of your request, the Collateral Agent, with
the consent of the Required Lenders, hereby grants to the Administrative
Borrower an extension of the date by which the Administrative Borrower must
submit the First Quarter Financial Statements from May 15, 2001 to May 30, 2001.


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Outsource International, Inc.
May 16, 2001
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                  Please note that the Collateral Agent's grant of an extension
at this time with respect to the First Quarter Financial Statements does not
obligate the Collateral Agent or the Required Lenders to grant any further or
other extensions. The failure by the Administrative Borrower to deliver the
First Quarter Financial Statements by May 30, 2001 may result in an Event of
Default under the Financing Agreement. In addition, the Collateral Agent and the
Required Lenders shall have no obligation to grant extensions with respect to
other obligations of the Loan Parties. Accordingly, this letter agreement is
without prejudice to the Agents and the Lenders and the Agents and the Lenders
reserve all of their rights under the Financing Agreement, the Loan Documents,
at law and otherwise regarding delivery of the First Quarter Financial
Statements or any other Events of Default that may exist. This letter agreement
shall not entitle the Administrative Borrower or any other Loan Party to any
other or further notice or demand regarding delivery of the First Quarter
Financial Statements or any other Events of Default that may exist.

                  Should the terms and conditions set forth herein meet with
your approval, please indicate your acceptance by signing and returning a copy
of this letter agreement to the Collateral Agent.

                [REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]



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Outsource International, Inc.
May 16, 2001
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                  This letter agreement (i) supersedes all prior discussions,
agreements, commitments, arrangements, negotiations or understandings, whether
oral or written, of the parties with respect thereto, (ii) shall be governed by
the law of the State of New York, without giving effect to the conflict of laws
provisions thereof, (iii) shall be binding upon the parties and their respective
successors and assigns, (iv) may not be relied upon or enforced by any other
person or entity, and (v) may be signed in multiple counterparts, each of which
shall be deemed an original and all of which together shall constitute one and
the same instrument. If this letter agreement becomes the subject of a dispute,
each of the parties hereto hereby waives trial by jury. This letter agreement
may be amended, modified or waived only in a writing signed by the parties
hereto.

                                                  Very truly yours,

                                                  ABLECO FINANCE LLC, as
                                                  Collateral Agent

                                                  By: /s/ ILLEGIBLE
                                                     --------------------------
                                                      Name:
                                                      Title:

Accepted and Agreed:

OUTSOURCE INTERNATIONAL, INC.,
as Administrative Borrower

By: /s/ GARRY E. MEIER
   ---------------------------------------------
     Name:
     Title:

cc:      Donn Beloff, Esq.
         Frederic Ragucci, Esq.