Quest Diagnostics Incorporated , the nation's leading provider of diagnostic testing, information and services, announced that it again was selected to be part of the Dow Jones Sustainability World Index (DJSI World). The company was first added to the index in 2004. In addition, Quest Diagnostics was selected for inclusion in the first Dow Jones Sustainability North America Index (DJSI North America).

"We are pleased to be selected again for the DJSI World Index and also included in the new North America Index," said Surya N. Mohapatra, Ph.D., Chairman and Chief Executive Officer of Quest Diagnostics. "We continue to drive our value proposition to create long-term value for our shareholders."

According to DJSI, companies were identified as "sustainability leaders" and ranked according to objective benchmarks linked to financial, environmental and social criteria. The DJSI defines corporate sustainability as "a business approach that creates long-term shareholder value by embracing opportunities and managing risks deriving from economic, environmental and social developments. Corporate sustainability leaders achieve long-term shareholder value by gearing their strategies and management to harness the market's potential for sustainability products and services while at the same time successfully reducing and avoiding sustainability costs and risks."

The DJSI World index was launched in 1999 as a way to help fund managers who base investment decisions on environmental and social factors as well as financial performance. The DJSI World Index contains more than 300 companies. The DJSI North America Index contains 111 companies -- 93 from the U.S. and 18 from Canada -- that were selected from among the largest 600 North American corporations. DJSI indexes are produced by Sustainable Asset Management Group, based in Zurich, Switzerland, together with Dow Jones Indexes and STOXX Limited. Additional information about the DJSI, including a list of all component companies, is available at: http://www.sustainability-indexes.com/.

About Quest Diagnostics

Quest Diagnostics is the leading provider of diagnostic testing, information and services that patients and doctors need to make better healthcare decisions. 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 a pioneer in developing innovative new diagnostic tests and advanced healthcare information technology solutions that help improve patient care. Additional company information is available at: http://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 2004 Form 10-K and subsequent filings.

SOURCE: Quest Diagnostics Incorporated

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

Web site: http://www.questdiagnostics.com/
http://www.sustainability-indexes.com/