SAN RAMON, Calif., Nov 11, 2005 /PRNewswire-FirstCall via COMTEX News Network/ -- Chevron Corporation (NYSE: CVX) announced today that Charles R. Williamson, executive vice president and former chairman of the board and chief executive officer of Unocal Corporation has elected to retire effective Dec. 1, 2005.

"Chuck has been a valuable, principled and respected leader in our industry. He has played an important role in helping ensure a seamless integration of Unocal into Chevron, which is now largely complete," said Dave O'Reilly, chairman and chief executive officer of Chevron Corporation. "Many of Chuck's accomplishments will contribute to Chevron's future growth, including his development of a leading international asset base, particularly in Southeast Asia and the Caspian region. We wish him well in his retirement."

"I am pleased to have contributed to this important transaction," said Williamson. "I leave knowing there is strong leadership in place and many exciting opportunities for Unocal's highly skilled employees who are now part of Chevron."

Williamson joined Union Oil Company of California (Unocal) as a research scientist in 1977 and worked on a wide range of research and technical applications with domestic and international exploration and production operations. In 1983, he was posted to London as Unocal's chief geologist for the United Kingdom and Ireland. In 1986, he was named exploration manager for Unocal Netherlands, where he served until 1989. From 1989 to 1992, he served as vice president of exploration for Unocal Thailand in Bangkok.

In 1992, Williamson was named vice president of technology and managed Unocal's upstream technology support and services. Williamson was appointed vice president of corporate planning and information services in 1994, and in 1995, he became vice president of corporate planning and economics. From 1996 until he was named chief executive officer of Unocal Corporation in January 2001, Williamson was group vice president and executive vice president for international energy operations. He served on Unocal's board of directors from 2000 to August 2005 and was chairman of the board from 2001 to 2005.

A native of Ohio, Williamson graduated from Wittenberg University in Springfield in 1970 with a bachelor's degree in geology. He obtained a master's degree in geology from the University of Utah in 1972 and joined Exxon Corporation in Houston, Texas. He served in various exploration and development assignments in the Gulf of Mexico and left Exxon in 1974 to attend the University of Texas at Austin. He obtained a Ph.D. in geology from the University of Texas at Austin in 1978.

Williamson has served as chairman of the US-ASEAN Business Council for the past three years and is a member of the board of directors of Weyerhaeuser Company and the American Petroleum Institute. He is a member of the National Petroleum Council and serves on several advisory boards, including those of the University of Texas at Austin and the Southern California Asia Society. He previously served on the Stanford University Earth Science advisory board.

Chevron Corporation is one of the world's leading energy companies. With more than 53,000 employees, Chevron subsidiaries conduct business in approximately 180 countries around the world, producing and transporting crude oil and natural gas, and refining, marketing and distributing fuels and other energy products. Chevron is based in San Ramon, Calif. More information on Chevron is available at www.chevron.com.

SOURCE Chevron Corporation