HOUSTON (AP) _ Dynegy Inc. has named president and chief executive Bruce Williamson as chairman of the board, replacing the retiring Daniel Dienstbier, officials announced Wednesday.

``Under Bruce's leadership, Dynegy has made outstanding progress in our self-restructuring plan, established a track record of delivering results, improved its capital structure and restored confidence and credibility with investors and the public,'' Dienstbier said.

Williamson, 44, has led Dynegy since October 2002.

Dienstbier, 63, spent nearly two years as chairman and nine years as a member of the board. He also served as interim chief executive from May 2002 until Williamson took over.

Dynegy's announcement comes as a number of U.S. companies are pushing corporate governance reforms such as separating the chairman and chief executive positions.

``The chairman role will leverage (Williamson's) proven leadership capabilities. The appointment also reflects our continued progress toward more 'normal' company operations,'' said Dynegy spokesman John Sousa. ``With our self restructuring plan essentially complete, (Williamson's) focus is more on growing value for our investors and positioning the company for the future, than on self restructuring 'to dos'.''

The Houston-based energy company also named board member Patricia Hammick, 57, as lead director in an effort to ensure that the board operates independently of management. She will preside over the regular executive sessions of Dynegy's independent directors.

The board intends to name Williamson and Hammick to their new positions following the annual shareholders meeting on May 20, as long as the company's shareholders re-elect them to serve as directors for another year.

Shares of Dynegy were down 6 cents to close at $3.46 on the New York Stock Exchange.