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EXHIBIT 4.2

FOURTH AMENDMENT TO CREDIT AGREEMENT

THIS FOURTH AMENDMENT TO CREDIT AGREEMENT, dated as of December 27, 1999, (the"Amendment"), is among
Alternative Resources Corporation, a Delaware corporation, the undersigned Lenders and American National Bank and Trust Company of Chicago, as Agent. Unless otherwise defined herein, capitalized terms
used herein shall have the meanings ascribed to them in Credit Agreement (as hereinafter defined).

W
I T N E S S E T H:

WHEREAS,
the Borrower, the Agent and the Lenders entered into that certain Credit Agreement dated as of November 7, 1997 as heretofore amended (as so amended and as the same
may hereafter be amended, modified, restated or otherwise supplemented from time to time, the"Credit Agreement");

WHEREAS,
the Borrower and the Lenders wish to make certain amendments to the Credit Agreement;

NOW,
THEREFORE, in consideration of the mutual covenants and agreements set forth herein and for other good and valuable consideration, the receipt and sufficiency of which hereby are
acknowledged, each of the undersigned agrees as follows:

1.Amendments to Credit Agreement.

(a) Section 6.10
of the Credit Agreement shall be amended in its entirety and as so amended shall read as follows:



(b) Section 6.16
of the Credit Agreement shall be amended in its entirety and as so amended to read as follows:



2.Representations.

In
order to induce the Lenders to execute and deliver this Amendment, the Borrower hereby represents to the Lenders that as of the date hereof, the representations and warranties set
forth in Article 5 of the Credit Agreement are and shall be and remain true and correct (except that the
representations contained in Section 5.4 shall be deemed to refer to the most recent financial statements of the Borrower delivered to the Lenders) and the Borrower is in compliance with all of
the terms and conditions of the Credit Agreement after giving effect to the amendments contemplated hereby and no Unmatured Default or Default has occurred and is continuing under the Credit Agreement
or shall result after giving effect to this Amendment.

3.Miscellaneous.

(a) This
Amendment shall become effective upon the execution and delivery hereof to the Agent by the Borrower and the Required Lenders.



(b) Except
as specifically amended herein, the Credit Agreement shall continue in full force and effect in accordance with its original terms. Reference to this
specific Amendment need not be made in any note, document, letter, certificate, the Credit Agreement itself, the Notes, any other Loan Document or any communication issued or made pursuant to or with
respect to the Credit Agreement, any reference in any of such to the Credit Agreement being sufficient to refer to the Credit Agreement as amended hereby.

(c) The
Borrower agrees to pay on demand all costs and expenses of or incurred by the Agent in connection with the negotiation, preparation, execution and delivery of
this Amendment, including the reasonable fees and expenses of counsel for the Agent.

(d) This
Amendment may be executed in any number of counterparts, and by the different parties on different counterparts, all of which taken together shall constitute
one and the same agreement. Any of the parties hereto may execute this Amendment by signing any such counterpart and each of such counterparts shall for all purposes be deemed to be an original. This
Amendment shall be governed by the internal laws of the State of Illinois.



IN
WITNESS WHEREOF, this Amendment has been duly executed by each of the undersigned as of the day and year first set forth above.

| |  |                                                                                           | 
| |  | ----------------------------------------------------------------------------------------- | 
| |  | ALTERNATIVE RESOURCES CORPORATION                                                        
| |  | By:
Name:
Its:                                                                            | 
| |  | AMERICAN NATIONAL BANK AND TRUST COMPANY OF CHICAGO,as Agent and individually as a Lender
| |  | By:
Name:
Its:                                                                            | 
| |  | MELLON BANK, N.A.                                                                        
| |  | By:
Name:
Its:                                                                            | 
| |  | HARRIS TRUST AND SAVINGS BANK                                                            
| |  | By:
Name:
Its:                                                                            | 
| |  | FLEET NATIONAL BANK                                                                      
| |  | By:
Name:
Its:                                                                            | 
| |  | NATIONAL CITY BANK                                                                       
| |  | By:
Name:
Its:                                                                            | 



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