                    POWER OF ATTORNEY


	Know all by these presents, that the undersigned
hereby constitutes and appoints each of Sirisha Gummaregula,
Michael E. Prevoznik, and Leo C. Farrenkopf, Jr., signing
singly, the undersigned's true and lawful attorney-in-fact
to:

(1)	execute for and on behalf of the undersigned, in
the undersigned's capacity as an executive officer and/or
director of Quest Diagnostics Incorporated (the "Company"),
Form ID Applications and Forms 3, 4 and 5 in accordance with
Section 16(a) of the Securities Exchange Act of 1934 and the
rules thereunder;

(2)	do and perform any and all acts for and on behalf
of the undersigned which may be necessary or desirable to
complete and execute any such Form ID Application, Form 3,
4 or 5, complete and execute any amendment or amendments
thereto, and timely  file such form with the United States
Securities and Exchange Commission and any other authority;
and

(3)	take any other action of any type whatsoever in
connection with the foregoing which, in the opinion of such
attorney-in-fact, may be of benefit to, in the best
interest of, or legally required by, the undersigned, it
being understood that the documents executed by such
attorney-in-fact on behalf of the undersigned pursuant to
this Power of Attorney shall be in such form and shall
contain such terms and conditions as such attorney-in-fact
may approve in such attorney-in-fact's discretion.

	The undersigned hereby grants to each such attorney-
in-fact full power and authority to do and perform all and
every act and thing whatsoever requisite, necessary and
properto be done in the exercise of any of the rights and
powers herein granted, as fully to all intents and purposes
as the undersigned might or could do if personally present,
with full power of substitution or revocation, hereby ratifying
and confirming all that such attorney-in-fact, or such attorney-
in-fact's substitute or substitutes, shall lawfully do or cause
to be done by virtue of this power of attorney and the rights
and powers herein granted.  The undersigned acknowledges that
the foregoing attorneys-in-fact,in serving in such capacity at
the request of the undersigned,are not assuming, nor is the
company assuming, any of the undersigned's responsibilities
to comply with Section 16 of the Securities Exchange Act of

1934.

	This Power of Attorney shall remain in full force and
effect until the undersigned is no longer required to file Forms
3, 4, and 5 with respect to the undersigned's holdings of and
transactions in securities issued by the Company, unless earlier
revoked by the undersigned in a signed writing delivered to the
foregoing attorneys-in-fact.

	IN WITNESS WHEREOF, the undersigned has caused this
Power of Attorney to be executed as of this 4th day of April,
2004.



	/s/ Gail R. Wilensky
	Signature
	GAIL R. WILENSKY



STATE OF MARYLAND	)
	 		):  ss.
COUNTY OF MONTGOMERY	)

	On this 14th  day of April, 2004, before me, the
subscriber,personally appeared GAIL R. WILENSKY, to me and
known to me to be the same person described in and who executed
the foregoing instrument, and she duly acknowledged to me that
she executed the same.


	/s/ Luz E. G. Mobin
	Notary Public
	Notary Public State of Maryland
	My Commission Expires January 1, 2006

