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                                                                Exhibit 10.8.15


                      FOURTH AMENDMENT TO CREDIT AGREEMENT

                  THIS FOURTH AMENDMENT TO CREDIT AGREEMENT (the
"AMENDMENT"), dated as of December 15, 1999, is entered into by and among
WESTAFF (USA), INC. ("WSS"), WESTERN MEDICAL SERVICES, INC. ("WMS" and
together with WSS, collectively, the "BORROWERS" and individually, a
"BORROWER"), BANK OF AMERICA, N.A., as agent for itself and the Banks (the
"AGENT"), and the several financial institutions party to the Credit
Agreement (collectively, the "BANKS").

                                    RECITALS

                  A. The Borrowers, Banks, and Agent are parties to a Credit
Agreement dated as of March 4, 1998, and amendments thereto dated as of May
15, 1998, July 23, 1998, and January 22, 1999 (collectively, the "CREDIT
AGREEMENT") pursuant to which the Agent and the Banks have extended certain
credit facilities to the Borrowers.

                  B. The Borrowers have requested that the Banks agree to
certain amendments of the Credit Agreement.

                  C. The Banks are willing to amend the Credit Agreement,
subject to the terms and conditions of this Amendment.

                                    AGREEMENT

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

                  1. DEFINED TERMS. Unless otherwise defined herein,
capitalized terms used herein shall have the meanings, if any, assigned to
them in the Credit Agreement.

                  2.  AMENDMENTS TO CREDIT AGREEMENT.

                           (a)  The first sentence of Section 8.13 of the
     Credit Agreement is amended to read as follows:

                           The Borrowers shall not, and shall not permit any
                           other Loan Party to, make or commit to make Capital
                           Expenditures in excess of an aggregate of Eight
                           Million Five Hundred Thousand Dollars ($8,500,000)
                           for the fiscal year ending October 30, 1999, and
                           Eight Million Dollars ($8,000,000) for each
                           subsequent fiscal year.

                  3.  REPRESENTATIONS AND WARRANTIES. The Borrowers each
hereby represent and warrant to the Agent and the Banks as follows:

                           (a) No Default or Event of Default has occurred and
         is continuing, except those Defaults or Events of Default, if any, that
         have been disclosed in writing to the Agent and the Banks or waived in
         writing by the Agent and the Banks.


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                           (b) The execution, delivery and performance by the
         Borrowers of this Amendment have been duly authorized by all necessary
         corporate and other action and do not and will not require any
         registration with, consent or approval of, notice to or action by, any
         Person (including any Governmental Authority) in order to be effective
         and enforceable. The Credit Agreement as amended by this Amendment
         constitutes the legal, valid and binding obligations of the Borrowers,
         enforceable against each of them in accordance with its respective
         terms, without defense, counterclaim or offset.

                           (c) All representations and warranties of the
         Borrowers contained in the Credit Agreement are true and correct.

                           (d) Each of the Borrowers is entering into this
         Amendment on the basis of its own investigation and for its own
         reasons, without reliance upon the Agent and the Banks or any other
         Person.

                  4. EFFECTIVE DATE. This Amendment will become effective as of
October 30, 1999 (the "EFFECTIVE DATE"), PROVIDED that each of the following
conditions precedent is satisfied on or before December 15, 1999:

                           (a) The Agent has received this Amendment duly
         executed by the Borrowers, the Agent, the Issuing Bank and each of the
         Banks, together with a duly executed Guarantor Acknowledgment and
         Consent in the form attached hereto.

                           (b) The Agent has received from WMS, Western Medical
         Services (NY), Inc., as a guarantor, and Alternative Billing Services,
         Inc., as a guarantor, a certificate of incumbency setting forth the
         names and specimen signatures of the authorized officers of each such
         corporation, certified by the Secretary or an Assistant Secretary of
         such corporation as of the date hereof.

                  5. RESERVATION OF RIGHTS. Each of the Borrowers
acknowledges and agrees that the execution and delivery by the Agent and the
Banks of this Amendment shall not be deemed to create a course of dealing or
otherwise obligate the Agent or the Banks to forbear or execute similar
amendments under the same or similar circumstances in the future.

                  6.  MISCELLANEOUS.

                           (a) Except as herein expressly amended, all terms,
         covenants and provisions of the Credit Agreement are and shall remain
         in full force and effect and all references therein to such Credit
         Agreement shall henceforth refer to the Credit Agreement as amended by
         this Amendment. This Amendment shall be deemed incorporated into, and a
         part of, the Credit Agreement.

                           (b) This Amendment shall be binding upon and inure to
         the benefit of the parties hereto and thereto and their respective
         successors and assigns. No third party beneficiaries are intended in
         connection with this Amendment.

                           (c) This Amendment shall be governed by and construed
         in accordance with the law of the State of California.


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                           (d) This Amendment may be executed in any number of
         counterparts, each of which shall be deemed an original, but all such
         counterparts together shall constitute but one and the same instrument.
         Each of the parties hereto understands and agrees that this document
         (and any other document required herein) may be delivered by any party
         thereto either in the form of an executed original or an executed
         original sent by facsimile transmission to be followed promptly by
         mailing of a hard copy original, and that receipt by the Agent of a
         facsimile transmitted document purportedly bearing the signature of a
         Bank or the Borrower or WMS shall bind such Bank or the Borrower or
         WMS, respectively, with the same force and effect as the delivery of a
         hard copy original. Any failure by the Agent to receive the hard copy
         executed original of such document shall not diminish the binding
         effect of receipt of the facsimile transmitted executed original of
         such document of the party whose hard copy page was not received by the
         Agent.

                           (e) This Amendment, together with the Credit
         Agreement, contains the entire and exclusive agreement of the parties
         hereto with reference to the matters discussed herein and therein. This
         Amendment supersedes all prior drafts and communications with respect
         thereto. This Amendment may not be amended except in accordance with
         the provisions of Section 11.01 of the Credit Agreement.

                           (f) If any term or provision of this Amendment shall
         be deemed prohibited by or invalid under any applicable law, such
         provision shall be invalidated without affecting the remaining
         provisions of this Amendment or the Credit Agreement, respectively.

                           (g) Each of the Borrowers covenants to pay to or
         reimburse the Agent, upon demand, for all costs and expenses (including
         allocated costs of in-house counsel) incurred in connection with the
         development, preparation, negotiation, execution and delivery of this
         Amendment, including without limitation appraisal, audit, search and
         filing fees incurred in connection therewith.

                  IN WITNESS WHEREOF, the parties hereto have executed and
delivered this Amendment as of the date first above written.

                                       WESTAFF (USA), INC.

                                       By /s/ Paul A. Norberg
                                          ------------------------
                                          Paul A. Norberg
                                          Executive Vice President and
                                          Chief Financial Officer

                                       By /s/ Michael W. Ehresman
                                          ------------------------
                                          Michael W. Ehresman
                                          Senior Vice President and
                                          Treasurer



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                                       WESTERN MEDICAL SERVICES, INC.

                                       By /s/ Gary A. Kittleson
                                          ------------------------
                                          Gary A. Kittleson
                                          Executive Vice President,
                                          Chief Financial Officer

                                       By /s/ Gary A. Kittleson
                                          ------------------------
                                          Gary A. Kittleson
                                          Secretary

                                       BANK OF AMERICA, N.A., as Agent

                                       By /s/ David Price
                                          ------------------------
                                          David Price
                                          Vice President

                                       BANK OF AMERICA, N.A., as a Bank and as
                                       Issuing Bank

                                       By /s/ Lisa M. Thomas
                                          ------------------------
                                          Lisa M. Thomas
                                          Vice President

                                       COMERICA BANK-CALIFORNIA, as a Bank

                                       By /s/ Scott T. Smith
                                          ------------------------
                                          Scott T. Smith
                                          Vice President

                                       SANWA BANK CALIFORNIA, as a Bank

                                       By /s/ Rochelle Dineen
                                          ------------------------
                                          Rochelle Dineen
                                          Vice President


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                      GUARANTOR ACKNOWLEDGMENT AND CONSENT

                The undersigned, each a guarantor or third party pledgor with
respect to the Borrowers' obligations to the Agent and the Banks under the
Credit Agreement, each hereby (i) acknowledges and consents to the execution,
delivery and performance by the Borrowers of the foregoing Fourth Amendment
to Credit Agreement (the "AMENDMENT"), and (ii) reaffirms and agrees that the
respective guaranty, third party pledge or security agreement to which the
undersigned is party and all other documents and agreements executed and
delivered by the undersigned to the Agent and the Banks in connection with
the Credit Agreement are in full force and effect, without defense, offset or
counterclaim. (Capitalized terms used herein have the meanings specified in
the Amendment.)

                                  WESTAFF, INC.

Dated: as of December 15, 1999    By /s/ Paul A. Norberg
       -----------------------       ----------------------------
                                     Paul A. Norberg
                                     Executive Vice President
                                     and Chief Financial Officer

                                  By /s/ Michael W. Ehresman
                                     ------------------------
                                     Michael W. Ehresman
                                     Senior Vice President and Treasurer

                                  WESTERN MEDICAL SERVICES (NY), INC.

Dated: as of December 15, 1999    By /s/ Gary A. Kittleson
       -----------------------       ----------------------------
                                     Gary A. Kittleson
                                     Executive Vice President and
                                      Chief Financial Officer

                                  By /s/ Gary A. Kittleson
                                     ----------------------------
                                     Gary A. Kittleson
                                     Secretary

                                  WESTERN TECHNICAL SERVICES, INC.

Dated: as of December 15, 1999    By /s/ Paul A. Norberg
       -----------------------       ----------------------------
                                     Paul A. Norberg
                                     Executive Vice President and
                                     Chief Financial Officer

                                  By /s/ Michael W. Ehresman
                                     ----------------------------
                                     Michael W. Ehresman
                                     Senior Vice President and Treasurer


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                                  MEDIAWORLD INTERNATIONAL

Dated: as of December 15, 1999    By /s/ Paul A. Norberg
       -----------------------       ----------------------------
                                     Paul A. Norberg
                                     Executive Vice President and
                                     Chief Financial Officer

                                  By /s/ Michael W. Ehresman
                                     ----------------------------
                                     Michael W. Ehresman
                                     Senior Vice President and Treasurer

                                  WESTAFF (GUAM), INC.

Dated: as of December 15, 1999    By /s/ Paul A. Norberg
       -----------------------       ----------------------------
                                     Paul A. Norberg
                                     Executive Vice President and
                                     Chief Financial Officer

                                  By /s/ Michael W. Ehresman
                                     ----------------------------
                                     Michael W. Ehresman
                                     Senior Vice President and Treasurer

                                  ALTERNATIVE BILLING SERVICES, INC.

Dated: as of December 15, 1999    By /s/ Gary A. Kittleson
       -----------------------       ----------------------------
                                     Gary A. Kittleson
                                     Executive Vice President and
                                     Chief Financial Officer

                                  By /s/ Gary A. Kittleson
                                     ----------------------------
                                     Gary A. Kittleson
                                     Secretary


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                                  BEST TEMPORARIES, INC.

Dated: as of December 15, 1999    By /s/ Paul A. Norberg
       -----------------------       ----------------------------
                                     Paul A. Norberg
                                     Executive Vice President and
                                     Chief Financial Officer

                                  By /s/ Michael W. Ehresman
                                     ----------------------------
                                     Michael W. Ehresman
                                     Senior Vice President and Treasurer

                                  BEST TEMPORARIES FEDERAL SYSTEMS, INC.

Dated: as of December 15, 1999    By /s/ Paul A. Norberg
       -----------------------       ----------------------------
                                     Paul A. Norberg
                                     Executive Vice President and
                                     Chief Financial Officer

                                  By /s/ Michael W. Ehresman
                                     ----------------------------
                                     Michael W. Ehresman
                                     Senior Vice President and Treasurer


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