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...

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.

(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.

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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/ ▇▇▇▇ ▇. ▇▇▇▇▇▇▇
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▇▇▇▇ ▇. ▇▇▇▇▇▇▇
Executive Vice President and
Chief Financial Officer

By /s/ ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇
------------------------
▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇
Senior Vice President and
Treasurer

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WESTERN MEDICAL SERVICES, INC.

By /s/ ▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
------------------------
▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
Executive Vice President,
Chief Financial Officer

By /s/ ▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
------------------------
▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
Secretary

BANK OF AMERICA, N.A., as Agent

By /s/ ▇▇▇▇▇ ▇▇▇▇▇
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▇▇▇▇▇ ▇▇▇▇▇
Vice President

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

By /s/ ▇▇▇▇ ▇. ▇▇▇▇▇▇
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▇▇▇▇ ▇. ▇▇▇▇▇▇
Vice President

COMERICA BANK-CALIFORNIA, as a Bank

By /s/ ▇▇▇▇▇ ▇. ▇▇▇▇▇
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▇▇▇▇▇ ▇. ▇▇▇▇▇
Vice President

SANWA BANK CALIFORNIA, as a Bank

By /s/ ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇
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▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇
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/ ▇▇▇▇ ▇. ▇▇▇▇▇▇▇
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▇▇▇▇ ▇. ▇▇▇▇▇▇▇
Executive Vice President
and Chief Financial Officer

By /s/ ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇
------------------------
▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇
Senior Vice President and Treasurer

WESTERN MEDICAL SERVICES (NY), INC.

Dated: as of December 15, 1999 By /s/ ▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
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▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
Executive Vice President and
Chief Financial Officer

By /s/ ▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
----------------------------
▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
Secretary

WESTERN TECHNICAL SERVICES, INC.