1987 (Apr) - 1989 (Jan)-Executive Officer, American Association for the Advancement of Science (AAAS) .
1989 (Jan) - 2000 (Mar)-Director, Oak Ridge National Laboratory (ORNL), Oak Ridge, TN, where he was responsible for programs that included applied research and engineering development in support of the Department of Energy's fusion, fission, conservation, and fossil energy technology programs [REF].