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                                                                    Exhibit 99.1

           QUEST DIAGNOSTICS TO COMPLETE CEO TRANSITION ON MAY 4, 2004
       -- Surya N. Mohapatra, Ph.D., to Become Chief Executive Officer --
          -- Kenneth W. Freeman to Continue as Chairman Of The Board --

TETERBORO, N.J., April 22, 2004-- Quest Diagnostics Incorporated (NYSE: DGX),
the nation's leading provider of diagnostic testing, information and services,
announced today that Surya N. Mohapatra, Ph.D., will be appointed President and
Chief Executive Officer on May 4, 2004, the date of the Annual Meeting of
Stockholders, completing the CEO succession plan announced in November, 2003.
Dr. Mohapatra, who is currently President and Chief Operating Officer, succeeds
Kenneth W. Freeman, who will continue as Chairman of the Board through December
14, 2004.

"The transition has gone extremely well," said Dan C. Stanzione, Ph.D., Lead
Independent Director and Governance Committee Chairman. "We look forward to
Surya's leadership and Ken's ongoing contributions as Chairman."

Under the succession plan announced in November, Mr. Freeman was expected to
remain as Chairman until May, 2005. However, as a result of a more rapid
transition of executive responsibilities, the Board and Mr. Freeman have agreed
that he will step down as Chairman several months sooner than originally planned
but will remain available to provide consulting services to the company through
early May, 2005. In connection with the accelerated transition, the company
expects to record pre-tax charges during the remainder of the year preliminarily
estimated to total $8.6 million, or $0.05 per diluted share, related to the
acceleration of certain pension obligations under the Executive Retirement
Supplemental Plan in which Mr. Freeman participates.

Dr. Mohapatra joined Quest Diagnostics in February, 1999, as Senior Vice
President and Chief Operating Officer and was appointed President in June, 1999.
He was elected to the Board of Directors in October, 2002. Over the past five
years, he has been responsible for the day-to-day management of Quest
Diagnostics and has played an important role in the growth and strategic
direction of the company.

Mr. Freeman joined Corning Clinical Laboratories, the predecessor company to
Quest Diagnostics, in May, 1995, after holding financial and general management
positions at Corning Incorporated from 1972. He became Chairman and CEO of Quest
Diagnostics at the end of 1996, when the company was spun off to Corning's
shareholders.

Quest Diagnostics Incorporated is the nation's leading provider of diagnostic
testing, information and services, providing insights that enable healthcare
professionals to make decisions that improve health. The company offers the
broadest access to diagnostic testing services through its national network of
laboratories and patient service centers, and provides interpretive consultation
through its extensive medical and scientific staff. Quest Diagnostics is the
leading provider of esoteric testing, including gene-based medical testing, and
provides advanced information technology solutions to improve patient care.
Additional company information is available at: www.questdiagnostics.com

The statements in this press release which are not historical facts or
information may be forward-looking statements. These forward-looking statements
involve risks and uncertainties that could cause actual results and outcomes to
be materially different. Certain of these risks




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and uncertainties may include, but are not limited to, competitive environment,
changes in government regulations, changing relationships with customers,
payers, suppliers and strategic partners and other factors described in the
Quest Diagnostics Incorporated 2003 Form 10-K and subsequent filings.

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