Quest Diagnostics Incorporated , the nation's leading provider of diagnostic testing, information and services, announced that it has been added to the Dow Jones Sustainability World Index (DJSI World), effective September 20.

The Index contains more than 300 companies identified as "sustainability leaders," 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."

"We are honored to be included in the Dow Jones Sustainability World Index," said Surya N. Mohapatra, Ph.D., President and Chief Executive Officer of Quest Diagnostics.

The DJSI World index was launched in 1999 as a way to help a growing number of fund managers who base investment decisions on environmental and social factors as well as financial performance. The index is 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 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: http://www.questdiagnostics.com/

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

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