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                                                                   EXHIBIT 10.12

                AMENDMENT NO. 1 TO LOAN AND SECURITY AGREEMENT

AMENDMENT NO. 1 dated as of January 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 (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 as follows:

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

                    "'Amendment No. 1' shall mean Amendment No. 1, dated as of
                    January 5, 2001, of this Agreement."

                    "'Amendment No. 1 Effective Date' shall mean the date on
                    which the amendments contemplated by Amendment No. 1 become
                    effective.";

          b.   subsection 1.1 of the Original Loan and Security Agreement is
               amended by amending and restating the definition of "Borrower"
               appearing therein as follows:

                    "'Borrower' and 'Borrowers' have the meaning assigned to
                    such terms in the preamble to this Agreement; provided,
                    however, that notwithstanding the foregoing, effective as of
                    December 14, 2000, Camelot Consulting Group, Inc. and
                    Camelot Group, Inc. are not Borrowers."

          c.   subsection 1.1 of the Original Loan and Security Agreement is
               amended by amending and restating the definition of "Inactive
               Subsidiary" appearing therein as follows:

                    "'Inactive Subsidiary' and 'Inactive Subsidiaries' have the
                    meanings assigned to such terms in the preamble to this
                    Agreement; provided, however, that notwithstanding the
                    foregoing, effective as of December 14, 2000, Camelot
                    Consulting Group, Inc. and Camelot Group, Inc. shall be
                    Inactive Subsidiaries."

          d.   subsection 1.1 of the Original Loan and Security Agreement is
               amended by amending and restating the definition of "Fee Letter"
               appearing therein as follows:

                    "'Fee Letter' means (i) prior to the Amendment No. 1
                    Effective Date, that certain letter agreement,
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                    among CC, COI, USI and the Administrative Agent, dated
                    December 14, 2000 and (ii) from and after the Amendment No.
                    1 Effective Date, the letter agreement referred to in the
                    foregoing clause (i) and the fee letter referred to in
                    paragraph 3(d) of Amendment No. 1."

          e.   subsection 2.1(A) of the Original Loan and Security Agreement is
               amended by substituting the figure "$100,000,000" appearing in
               the first paragraph thereof, with the figure "$110,000,000";

          f.   subsection 7.6(B) of the Original Loan and Security Agreement is
               amended by (i) deleting the word "and" appearing at the end of
               clause (8) thereof, (ii) substituting the phrase "; and" for the
               period appearing at the end of clause (9) thereof and (iii)
               adding the following immediately following the end of clause (9)
               thereof: " pro forma EBITDA of the Target (giving effect to the
               proposed Permitted Acquisition as of the first day of such twelve
               fiscal month period), for the period of twelve consecutive fiscal
               months for which financial statements are available and which
               ended most recently prior to the date on which notice of such
               proposed Permitted Acquisition was given to the Administrative
               Agent in accordance with clause (1) of this subsection 7.6(B),
               shall have been not less than $1.00, and a Borrower
               Representative shall have demonstrated to the satisfaction of the
               Administrative Agent (through delivery of financial statements
               and other information or otherwise), at least five (5) Business
               Days prior to the date of consummation of such proposed Permitted
               Acquisition, that EBITDA of the Target for such period shall
               satisfy the requirement of this clause (10)."

          g.   subsection 9.2(H)(1)(y) of the Original Loan and Security
               Agreement is amended by replacing the phrase "Requisite Lenders"
               appearing therein with the phrase "the Lenders";

          h.   subsection 9.8 of the Original Loan and Security Agreement is
               amended by adding the following immediately prior to the period
               ending such subsection: "; any such Revolving Advance made under
               this subsection 9.8 being due and payable upon demand by
               Administrative Agent; provided, however, that notwithstanding the
               foregoing, in the event that the Revolving Loan exceeds, on the
               thirtieth day following the making of any such Revolving Advance,
               the limitation set forth in subsection 2.1(A)(1)(b), such
               Revolving Advance, to the extent not theretofore paid, shall
               become due and payable on such thirtieth day"; and

          i.   the figure "$33,333,334.00" appearing below the phrase "Revolving
               Loan Commitment" below the signature of IBJW on the signature
               page of the Original Loan and Security Agreement is replaced by
               the figure "$43,333,334.00".

     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. 1.

                    b.   this Amendment No. 1 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. 1 will not violate any law, statute or
                         regulation applicable to any Loan Party, or any order
                         or decree of any court or governmental instrumentally
                         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.
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     3.   Effectiveness. The foregoing amendments contained in this Amendment
No. 1 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 January 5, 2001:

          a.   this Amendment No. 1 shall have been executed and delivered by
               each Loan Party and all Lenders;

          b.   as of the Effective Date, there shall be continuing no Default or
               Event of Default (other than the Defaults and Events of Default
               which are the subject of the waivers set forth herein);

          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);

          d.   IBJW shall have received from CC, COI and USI, a fee letter,
               dated the Effective Date, and in form and substance satisfactory
               to IBJW;

          e.   the Administrative Agent shall have received a legal opinion,
               dated the Effective Date, from independent counsel to the Loan
               Parties, as to the Original Loan and Security Agreement, as
               amended by this Amendment No. 1 and the other Loan Documents, in
               substantially the form of the opinion delivered by such counsel
               on the Closing Date; and

          f.   IBJW shall have received a Revolving Note (in substantially the
               same form as that issued by the Borrowers to IBJW on the Closing
               Date), dated the Closing Date, in the maximum principal amount of
               $43,333,334.00, by the Borrowers to the order of IBJW (and
               concurrently with such delivery, IBJW shall return the Revolving
               Note delivered to it on the Closing Date, marked "Cancelled and
               Replaced").

     4    Governing Law. This Amendment No. 1 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. 1 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. 1 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 as amended by this Amendment No. 1 (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. 1
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 to Amendment No. 1]

                              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: