Quest Diagnostics Incorporated , the nation's leading provider of diagnostic testing, information and services, announced that David M. Zewe, Senior Vice President, Diagnostic Testing Operations, and Laure E. Park, Vice President, Investor Relations, are scheduled to speak at the Morgan Stanley Second Annual Global Healthcare Unplugged Conference on Thursday, May 6, 2004, at The Mandarin Oriental Miami, in Miami, Florida. The Quest Diagnostics presentation is scheduled to begin at 10:30 a.m. Eastern Time.

The presentation will be webcast live during the conference and will be available to registered investors on the following site: http://customer.talkpoint.com/MORG007/050504a_cf/default.asp?entity=quest and to the public on http://www.questdiagnostics.com/. In addition, the archived webcast will be available starting by the end of the day, and will be available for 30 days.

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 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.

SOURCE: Quest Diagnostics Incorporated

CONTACT: Laure Park (Investors), +1-201-393-5030, or Gary Samuels
(Media), +1-201-393-5700, both for Quest Diagnostics Incorporated

Web site: http://www.questdiagnostics.com/