<PAGE>
                                                                   EXHIBIT 10.18

                    SETTLEMENT AGREEMENT AND MUTUAL RELEASE


          THIS SETTLEMENT AGREEMENT AND MUTUAL RELEASE ("Settlement Agreement")
is dated as of December 21, 2000, by and among COMSYS INFORMATION TECHNOLOGY
SERVICES, INC. ("Comsys"), COTELLIGENT, INC. ("Cotelligent, Inc.") and
COTELLIGENT USA, INC. ("Cotelligent USA" and, together with Cotelligent, Inc.,
"Cotelligent"). Cotelligent, Inc., Cotelligent USA and Comsys are individually
referred to as a "Party" and collectively referred to as the "Parties".

                                    RECITALS

          WHEREAS, Cotelligent, Inc., Cotelligent USA and Comsys entered into
that certain Asset Purchase Agreement, dated as of June 14, 2000 (the "Asset
Purchase Agreement"), whereby Comsys acquired from Cotelligent the Acquired
Assets for the Purchase Price;

          WHEREAS, capitalized terms used herein but not otherwise defined shall
have the meanings given to such terms in the Asset Purchase Agreement;

          WHEREAS, pursuant to Section 2.3(b)(i) of the Asset Purchase
Agreement, and subject to the terms and conditions of that certain Escrow
Agreement dated as of June 30, 2000 (the "Escrow Agreement") by and among the
Parties and American National Bank and Trust Company of Chicago (the "Escrow
Agent"), a portion of the Purchase Price in the aggregate amount of $5,000,000
was deposited into the Escrow Account at the Closing (the "Escrow Deposit");

          WHEREAS, certain disputes have arisen between Cotelligent and Comsys
in connection with the adjustment of the Purchase Price and computation of the
Earn Out contemplated by Section 2.2 of the Asset Purchase Agreement and with
respect to certain indemnity claims asserted by Comsys pursuant to Article VIII
of the Asset Purchase Agreement (collectively, the "Disputes");

          WHEREAS, the Disputes are more specifically set forth and detailed in
(i) that certain letter dated September 15, 2000, from Comsys to Cotelligent,
with respect to the Draft Computations, (ii) that certain letter dated October
13, 2000, from Cotelligent to Comsys, setting forth the Objection Notice, and
(iii) that certain letter dated November 27, 2000, from Comsys to Cotelligent,
setting forth indemnity claims (collectively, the "Dispute Letters"); and

          WHEREAS Cotelligent and Comsys now desire to settle fully and finally
the Disputes and the differences set out in the Dispute Letters on the terms and
conditions hereinafter set forth.

          NOW, THEREFORE, in consideration of the foregoing and the mutual
covenants contained herein, and in exchange for good and valuable consideration,
the receipt and adequacy of which are hereby acknowledged, the Parties hereby
agree as follows:

          1.  RELEASE OF ESCROW FUND AND TERMINATION OF ESCROW AGREEMENT.
Comsys, Cotelligent, Inc. and Cotelligent USA agree to execute and deliver to
the Escrow Agent
<PAGE>

a joint instruction letter, in substantially the form of Exhibit A attached
hereto (the "Joint Instruction Letter"), instructing the Escrow Agent to (a)
immediately release the entire Escrow Deposit, together with all products and
proceeds thereof, including all accrued interest, dividends, gain and other
income earned from time to time with respect thereto (collectively, the "Escrow
Fund") to Cotelligent, and (b) thereafter close the Escrow Account. The Joint
Instruction Letter shall be delivered in accordance with Section 8 of the Escrow
Agreement.

          2.  RELEASES BY COMSYS. Effective upon receipt by Cotelligent of the
Escrow Fund, Comsys, on behalf of itself and its successors and assigns, hereby
forever fully releases and discharges Cotelligent, Inc. and Cotelligent USA,
each of their respective affiliates, successors and assigns and each of their
respective present and former directors, officers, employees, trustees, agents,
attorneys, insurers, and affiliated entities, shareholders, representatives,
predecessors, successors and assigns, and any related entities and subsidiaries
(collectively, the "Cotelligent Released Parties") from and against all
liabilities, claims, causes of action, charges, complaints, grievances,
obligations, costs, losses, damages, injuries, attorneys' fees, and other legal
responsibilities of any form whatsoever ("Claims") which Comsys now has, owns,
or holds, or claims to have owned or held, or which Comsys at any time
heretofore had, owned, or held, or claimed to have, own, or hold, against the
Cotelligent Released Parties, with respect to (a) the Disputes, including,
without limitation, any payment obligations pursuant to Section 2.2 of the Asset
Purchase Agreement, (b) the matters referenced in the Dispute Letters, (c)
indemnification under Section 8.2(a)(i) of the Asset Purchase Agreement, and (d)
that certain side letter dated June 30, 2000, from Cotelligent to Comsys, with
respect to consents and estoppel agreements (collectively, the "Comsys Released
Claims").

          3.  RELEASES BY COTELLIGENT. Effective upon receipt by Cotelligent of
the Escrow Fund, Cotelligent, on behalf of itself and its successors and
assigns, hereby forever releases and discharges Comsys, its affiliates,
successors and assigns and each of their respective present and former
directors, officers, employees, trustees, agents, attorneys, insurers, and
affiliated entities, shareholders, representatives, predecessors, successors and
assigns, and any related entities and subsidiaries (collectively, the "Comsys
Released Parties") from and against  all of the Claims which Cotelligent now
has, owns, or holds, or claims to have owned or held, or which Comsys at any
time heretofore had, owned, or held, or claimed to have, own, or hold, against
the Comsys Released Parties, with respect to (a) the Disputes, including,
without limitation, any payment obligations pursuant to Section 2.2 of the Asset
Purchase Agreement, (b) the matters referenced in the Dispute Letters, (c)
indemnification under Section 8.2(c)(i) of the Asset Purchase Agreement
(collectively, the "Cotelligent Released Claims").

          4.  NO TRANSFER OF RELEASED CLAIMS.  Cotelligent covenants that it has
neither assigned, transferred nor purported to assign or transfer to any Person
any of the Cotelligent Released Claims. Comsys covenants that it has neither
assigned, transferred nor purported to assign or transfer to any Person any of
the Comsys Released Claims.

          5.  NO ACTIONS BASED ON RELEASED CLAIMS.  Cotelligent covenants and
agrees not to commence or prosecute any action or suit on the account of any of
the Cotelligent Released Claims. Comsys covenants and agrees not to commence or
prosecute any action or suit on the account of any of the Comsys Released
Claims.

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          6.  RELEASE COVERS UNKNOWN CLAIMS.  The Cotelligent Released Claims
and the Comsys Released Claims are intended to cover all Claims within the scope
of the release whether the same are known or unknown or ascertained or
unascertained.  The Parties agree that any provision of law that provides that a
general release does not extend to claims which the creditor does not know or
suspect to exist in his favor at the time of executing the release, which if
known by him must have materially affected his settlement with the debtor, is
hereby specifically waived by each Party.  Cotelligent and Comsys acknowledge
that one or the other may hereafter discover facts different from or in addition
to those which it now knows or believes to be true with respect to the matters
released herein, and agree that this Settlement Agreement shall be and remain
effective in all respects notwithstanding such different or additional facts or
the discovery hereof.

          7.  THE RELEASES. Notwithstanding the above, these releases do not
impair (a) the Parties' respective rights and obligations set forth in this
Settlement Agreement or (b) other than with respect to the Cotelligent Released
Claims and the Comsys Released Claims, the Parties' respective rights and
obligations set forth in the Asset Purchase Agreement.

          8.  GOVERNING LAW.  This Settlement Agreement shall be governed by and
construed under the laws of the State of Delaware.

          9.  ENTIRE AGREEMENT.  This Settlement Agreement sets forth the full
and complete understanding of the Parties relating to the subject matter hereof
as of the date hereof, and supersedes any and all negotiations, agreements and
representations made or dated prior thereto.

          10.  MODIFICATION.  No supplement, modification or amendment of this
Settlement Agreement shall be binding on the Parties unless executed in writing
by all the Parties.  No waiver of the provisions of this Settlement Agreement by
any Party shall be deemed to constitute a waiver of any other provisions,
whether or not similar, nor shall any waiver constitute a continuing waiver.  No
waiver shall be binding unless executed in writing by the Parties making the
waiver.

          11.  BINDING EFFECT.  This Settlement Agreement shall be binding on
and shall inure to the benefit of the successors, representatives and assigns of
the Parties.

          12.  SEVERABILITY.  Any provision of this Settlement Agreement which
is prohibited or unenforceable shall be ineffective to the extent of such
prohibition or unenforceability without invalidating the remaining provisions
hereof.

          13.  CONFIDENTIALITY.  Without the prior written consent of each of
the other Parties to this Settlement Agreement, no Party shall disclose the
provisions of this Settlement Agreement to any third party (other than such
Party's attorneys, accountants, tax consultants or other advisors), except (a)
as necessary for enforcing the terms of this Settlement Agreement in the course
of any legal proceedings, or (b) if required by law, but, in such case, only
that information necessary for compliance with such legal requirement may be
disclosed and only to those entitled to receive it, and the Party disclosing the
information shall take appropriate measures to require the recipients to
preserve the information's confidentiality.  Notwithstanding

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<PAGE>

anything herein to the contrary, Cotelligent shall have the right to file this
Settlement Agreement in public securities filings with governmental authorities
(or otherwise publicly disclose the terms hereof in order to meet requirements
applicable to reporting companies), to the extent legally required in the
opinion of legal counsel to Cotelligent.

          14.  TRANSACTION COSTS.  Each party shall pay its own fees and
expenses incurred in connection with the preparation and negotiation of this
Settlement Agreement and the consummation of the transactions contemplated
hereby.

          15.  CAPTIONS AND EXHIBITS.  Titles or captions of Sections contained
in this Settlement Agreement are included only as a matter of convenience and
for reference, and in no way define, limit, extend, describe or otherwise affect
the scope or meaning of the Settlement Agreement or the intent of any provision
hereof.

          16.  COUNTERPARTS.  This Settlement Agreement may be executed in
identical counterparts, all of which shall constitute duplicate originals.



          [ Remainder of Page Intentionally Left Blank ]

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<PAGE>

IN WITNESS WHEREOF, the parties have executed this Settlement Agreement as of
the date first written above.


                              COTELLIGENT, INC.


                              By: /S/ JAMES R. LAVELLE
                                  ___________________________
                              Name: James R. Lavelle
                              Title: Chairman & Chief Executive Officer

                              COTELLIGENT USA, INC.


                              By: /S/ JAMES R. LAVELLE
                                  ___________________________
                              Name: James R. Lavelle
                              Title: Chief Executive Officer



                              COMSYS INFORMATION TECHNOLOGY
                              SERVICES, INC.


                              By: /S/ AMIR ALAVI
                                  _____________________________
                              Name: Amir Alavi
                              Title: Senior Vice President

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<PAGE>

                                    EXHIBIT

                        FORM OF JOINT INSTRUCTION LETTER

To:       American National Bank and Trust Company of Chicago
          120 South LaSalle Street, 4th Floor
          Corporate Trust Department; Mail Code IL1-1250
          Chicago, IL 60603

          Attention: Timothy P. Martin
          Telecopy: 312-661-6491


From:     COMSYS Information Technology Services, Inc.
          4400 Post Oak Parkway, Suite 2575
          Houston, Texas 77027

          Cotelligent, Inc.
          101 California Street, Suite 2050
          San Francisco, California 94111

          Cotelligent USA, Inc.
          101 California Street, suite 2050
          San Francisco, California 94111


RE: ACCOUNT #44475002

Ladies and Gentlemen:

     We refer to account # 44475002 (the "Escrow Account") and that certain
Escrow Agreement dated as of June 30, 2000 by and among COMSYS Information
Technology Services, Inc., Cotelligent, Inc., Cotelligent USA, Inc. and American
National Bank and Trust Company of Chicago (the "Escrow Agreement").
Capitalized terms used hereinafter and not otherwise defined shall have the
meanings given to them in the Escrow Agreement.

     We hereby instruct you to immediately remit the balance of the funds in the
Escrow Account as of the date hereof (the "Escrow Proceeds"), in immediately
available funds, to the following account of Cotelligent, Inc.:

       USBank
       1420 Fifth Avenue
       Seattle, WA 98101

       Account number 1-535-0178-6609
       ABA Routing 125-000-105

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<PAGE>

       Reference: Comsys Escrow Balance

       Customer Representative: Rebecca Kwan
                                Tel: 206-587-5230
                                Fax 206-587-5280

     Any and all accrued interest (including the interest accrued on the Escrow
Proceeds during the month of December), dividends, gain and other income earned
on the Escrow Proceeds but not credited to the Escrow Account as of the date
hereof (the "Additional Interest") shall be remitted to the aforementioned
account of Cotelligent, Inc. as soon as reasonably possible thereafter.

     Upon receipt of the Escrow Proceeds and the Additional Interest by
Cotelligent, please proceed to close the Escrow Account.

     We hereby also confirm that, upon the receipt of the Escrow Proceeds and
the Additional Interest by Cotelligent, the Escrow Agreement is terminated and
you are irrevocably and unconditionally released of all obligation and
liabilities arising therefrom.

     Yours faithfully,


     COMSYS INFORMATION TECHNOLOGY SERVICES, INC.


     By: /s/ AMIR ALAVI
         ---------------------------
     Name:  Amir Alavi
     Title: Senior Vice President

     COTELLIGENT, INC.


     By: /s/ JAMES R. LAVELLE
         ---------------------------
     Name:  James R. Lavelle
     Title: Chairman & Chief Executive Officer

     COTELLIGENT USA, INC.


     By: /s/ JAMES R. LAVELLE
         ---------------------------
     Name:  James R. Lavelle
     Title: Chairman & Chief Executive Officer

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