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                                                                   EXHIBIT 10.13

                AMENDMENT NO. 2 TO LOAN AND SECURITY AGREEMENT

AMENDMENT NO. 2 dated as of March 5, 2001 to LOAN AND SECURITY AGREEMENT dated
as of December 14, 2000 among COMFORCE CORPORATION, COMFORCE OPERATING, INC. and
UNIFORCE SERVICES, INC. (the "Holding Companies"), certain direct and indirect
subsidiaries of the Holding Companies (the "Other Loan Parties"), the Lenders
whose signatures appear below, TRANSAMERICA BUSINESS CREDIT CORPORATION, as Co-
Agent (the "Co-Agent"), THE CIT GROUP/BUSINESS CREDIT, INC., as Collateral Agent
(the "Collateral Agent") and IBJ WHITEHALL BUSINESS CREDIT CORPORATION, as
Administrative Agent for the benefit of itself and the Lenders (the
"Administrative Agent").

                             Preliminary Statement

 .     The Holding Companies, the Other Loan Parties, the Co-Agent, the
      Collateral Agent, the Administrative Agent, and the Lenders (as defined
      therein) have entered into a Loan and Security Agreement dated as of
      December 14, 2000, as amended as of January 5, 2001 and as may be further
      amended, restated, supplemented or otherwise modified from time to time
      (the "Original Loan and Security Agreement"; terms defined in the Original
      Loan and Security Agreement and not otherwise defined herein shall have
      the meanings assigned thereto in the Original Loan and Security
      Agreement).

 .     The Loan Parties, and Lenders desire to amend the Original Loan and
      Security Agreement as provided herein.

NOW, THEREFORE, in consideration of the premises set forth herein, the Loan
Parties and the Lenders hereby agree as follows:

1.    Amendments. The Original Loan and Security Agreement is, subject to the
satisfaction of the conditions referred to below, amended and restated in its
entirety as follows:

  a.  Paragraph (2) of the Recitals to the Original Loan and Security Agreement
      is amended and restated as follows:

      "Holding Parties and Borrowers desire that Lenders extend a credit
      facility to Borrowers to i) acquire and retire in one or more purchases
      Senior Notes at a discounted purchase price as permitted by this Agreement
      (the 'Senior Note Prepayment' ) and to pay related tax expenses; ii)
      acquire and retire in one or more purchases Senior PIK Notes held by any
      Person not employed by a Loan Party as of the Amendment No. 2 Effective
      Date, at a discounted purchase price as permitted by this Agreement (the
      'Senior PIK Note Prepayment' ) and to pay related tax expenses; iii) to
      refinance certain indebtedness of Borrowers; and iv) to provide financing
      for working capital and for general corporate purposes from time to time
      to Borrowers and their Subsidiaries;".

  b.  the following definitions are added to subsection 1.1 of the Original Loan
      and Security Agreement in their respective proper alphabetical places:

      "'Amendment No. 2' shall mean Amendment No. 2, dated as of March 5, 2001,
      of this Agreement."

      "'Amendment No. 2 Effective Date' shall mean the date on which the
      amendments contemplated by Amendment No. 2 become effective."

      "'Senior PIK Note Prepayment' has the meaning assigned to such term in
      the preamble to this Agreement."

  c.  subsection 1.1 of the Original Loan and Security Agreement is amended by
      amending the definition of "Fixed Charges" appearing therein by adding the
      phrase "and/or the acquisition, prepayment or retirement of Senior PIK
      Notes" immediately after the phrase "non-recurring gain associated with
      the acquisition,

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      prepayment or retirement of Senior Notes" appearing therein;

   d. subsection 2.5 of the Original Loan and Security Agreement is amended and
      restated in its entirety as follows:

      "Borrower shall utilize the proceeds of the Revolving Loan solely (i) for
      the Senior Note Prepayment; (ii) for the Senior PIK Note Prepayment; (iii)
      to refinance senior revolving debt of the Borrowers; and (iv) to provide
      working capital and for general corporate purposes from time to time for
      CC and its Subsidiaries. Prior to and as a condition to the making of the
      Revolving Loan, a Borrower Representative will, as of the Closing Date,
      deliver to Administrative Agent a funds flow memorandum detailing how
      funds from the Revolving Loan are to be transferred to particular uses.";

   e. subsection 3.1(M) of the Original Loan and Security Agreement is amended
      by (1) substituting the word "and" after the phrase "Consent
      Solicitations" appearing therein with a comma and (2) adding the phrase
      "and Senior PIK Note Prepayment" immediately after the phrase "Senior Note
      Prepayment" appearing therein;

   f. subsection 4.16 of the Original Loan and Security Agreement is amended by
      (1) substituting the word "and" after the phrase "Consent Solicitations"
      appearing therein with a comma and (2) adding the phrase "and Senior PIK
      Note Prepayment" immediately after the phrase "Senior Note Prepayment"
      appearing therein; and

   g. subsection 7.5 of the Original Loan and Security Agreement is amended by
      amending and restating clause (A) appearing therein in its entirety as
      follows:

      "to effect the Senior Note Prepayment and/or Senior PIK Note Prepayment so
      long as (i) immediately after giving effect to either the Senior Note
      Prepayment and/or Senior PIK Note Prepayment, there shall be Unused
      Availability equal to the sum of (w) $10,000,000 plus (x) the tax expense
      of CC and its Subsidiaries related to any non-recurring gain arising from
      such Senior Note Prepayment and/or Senior PIK Note Prepayment plus (y)
      accrued and unpaid interest (other than interest payable in kind) on the
      Senior Notes and Senior PIK Notes, (ii) the total cost of such Senior PIK
      Note Prepayment, including such tax expenses and all other costs and
      expenses paid or incurred in connection with such Senior PIK Note
      Prepayment shall not exceed $9,000,000, (iii) the total cost of such
      Senior Note Prepayment plus the Senior PIK Note Prepayment, including such
      tax expenses and all other costs and expenses paid or incurred in
      connection with such Senior Note Prepayment and/or Senior PIK Note
      Prepayment shall not exceed $16,500,000 in the aggregate, and (iv) the
      Senior Note Prepayment and/or Senior PIK Note Prepayment shall comply with
      all applicable laws and terms of all agreements (including the Senior
      Notes Indenture and Senior Debentures Indenture) to which CC or any of its
      Subsidiaries is a party or by which any of them is bound; and".

2. Representations and Warranties.  Each Loan Party represents and warrants
(which representations and warranties shall survive the execution and delivery
hereof) to the Lenders that:

   a. no consent of any other person, including, without limitation,
      shareholders or creditors of any Loan Party is required to authorize, or
      is otherwise required in connection with the execution, delivery and
      performance of this Amendment No. 2.

   b. this Amendment No. 2 has been duly executed and delivered by a duly
      authorized officer of each Loan Party, and constitutes the legal, valid
      and binding obligations of such Loan Party, enforceable against such party
      in accordance with its terms, except as enforcement thereof may be subject
      to the effect of any applicable (i) bankruptcy, insolvency,
      reorganization, moratorium or similar law affecting creditors' rights
      generally and (ii) general principles of equity (regardless of whether
      enforcement is sought in a proceeding in equity or at law).

   c. the execution, delivery and performance of this Amendment No. 2 will not
      violate any law, statute or regulation applicable to any Loan Party, or
      any order or decree of any court or governmental instrumentally
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      applicable to such company, or conflict with, or result in the breach of,
      or constitute a default under any contractual obligation of such company,
      including the Loan Documents.

3. Effectiveness. The foregoing amendments contained in this Amendment No. 2 to
the Original Loan and Security Agreement shall become effective upon the
satisfaction in full of the following conditions on a date (the "Effective
Date") on or before March 5, 2001:

   a. this Amendment No. 2 shall have been executed and delivered by each Loan
      Party and the Requisite Lenders as set forth on the signature pages
      hereto;

   b. as of the Effective Date, there shall be continuing no Default or Event of
      Default;

   c. the representations made by the Loan Parties herein and in the Loan
      Documents shall be true in all respects as of the Effective Date (except
      as to any representation or warranty limited to a specific earlier date);
      and

4. Governing Law.  This Amendment No. 2 to the Original Loan and Security
Agreement is being delivered in the State of New York and shall be governed by
and construed in accordance with the laws of the State of New York.

5. Counterparts.  This Amendment No. 2 to the Original Loan and Security
Agreement is being executed by the parties hereto in separate counterparts, each
of which when so executed and delivered shall be deemed an original, but all of
which counterparts together shall constitute but one and the same instrument.

6. Consent. By signing below, each Loan Party consents to the execution and
delivery of this Amendment No. 2 by each other Loan Party and agrees that the
obligations of such Loan Party under the Loan Documents continue in full force
and effect.

7. Miscellaneous. All references in the Loan Documents to the "Loan and Security
Agreement" and in the Original Loan and Security Agreement to "this Agreement,"
"hereof," "herein" or the like shall mean and refer to the Original Loan and
Security Agreement and this Amendment No. 2 (as well as by all subsequent
amendments, restatements, modifications and supplements thereto).

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IN WITNESS WHEREOF, the Loan Parties, the Lenders, the Co-Agent, the Collateral
Agent and the Administrative Agent have caused this Amendment No. 2 to the
Original Loan and Security Agreement to be executed as of the day and year first
written above.



Holding Parties:              COMFORCE CORPORATION
                              COMFORCE OPERATING, INC.

Borrowers:                    BRENTWOOD OF CANADA, INC.
                              BRENTWOOD SERVICE GROUP, INC.
                              CAMELOT COMMUNICATIONS GROUP, INC.
                              CAMELOT CONTROL GROUP, INC.
                              CLINICAL LABFORCE OF AMERICA, INC.
                              COMFORCE INFORMATION TECHNOLOGIES, INC.
                              COMFORCE TECHNICAL ADMINISTRATIVE SERVICES, INC.
                              COMFORCE TECHNICAL SERVICES, INC.
                              COMFORCE TELECOM, INC.
                              GERRI G., INC.
                              LABFORCE OF AMERICA, INC.
                              PRO SERVICES, INC.
                              PRO UNLIMITED, INC.
                              PRO UNLIMITED SERVICES, INC.
                              SUMTEC CORPORATION
                              TEMPORARY HELP INDUSTRY SERVICING COMPANY, INC.
                              THISCO OF CANADA, INC.
                              UNIFORCE PAYROLLING SERVICES, INC.
                              UNIFORCE PAYROLLING TRI-STATE INC.
                              UNIFORCE SERVICES, INC.
                              UNIFORCE STAFFING SERVICES, INC.

Inactive Subsidiaries:        COMFORCE ACQUISITION 1 CORP.

                   [Signatures Continued on Following Page]

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                    [Signature page 1 of 2 to Amendment No. 2]


                              For each of the foregoing corporations:

                              By:  __________________________________________
                                   Name:
                                   Title:

                              IBJ WHITEHALL BUSINESS CREDIT CORPORATION, as
                              Administrative Agent and Lender

                              By:   _________________________________________
                                    Name:
                                    Title:

                              THE CIT GROUP/BUSINESS CREDIT, INC.,

                              as Collateral Agent and Lender

                              By:   _________________________________________
                                    Name:
                                    Title:

                              TRANSAMERICA BUSINESS CREDIT CORPORATION, as Co-
                              Agent and Lender

                              By:   _________________________________________
                                    Name:
                                    Title:

                              FLEET CAPITAL CORPORATION, as Lender

                              By:   _________________________________________
                                    Name:
                                    Title:


                   [Signatures Continued on Following Page]

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                   [Signature page 2 of 2 to Amendment No. 2]


                              GUARANTY BUSINESS CREDIT CORPORATION, as Lender

                              By:   _________________________________________
                                    Name:
                                    Title:

                              LASALLE BUSINESS CREDIT, INC, as Lender

                              By:   _________________________________________
                                    Name:
                                    Title:

                              THE CHASE MANHATTAN BANK, as Lender

                              By:   _________________________________________
                                    Name:
                                    Title:

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