- Chandra X-ray Observatory Cycle 3 Peer Review, 2001
- Panel Chair, Chandra X-ray Observatory Cycle 3 Cost Review, 2001
- Kitt Peak National Observatory Extragalactic Time Allocation Committee, 2001-2004
- National Radio Astronomy Observatory Time Allocation Review Committee, 2002-2004
- Hubble Space Telescope Extragalactic Panel, 2004
- Panel Chair, Chandra X-ray Observatory Cycle 5 Peer Review, 2003
- Panel Chair, Chandra X-ray Observatory Cycle 5 Cost Review, 2003
- Constellation-X Observatory Facility Science Team Panel, 2003--
- Scientific Organizing Committee for ``The Riddle of Cooling Flows in Galaxies and Clusters of Galaxies'', held in Charlottesville, VA, May 31-June 4, 2003
- Co-Chair, Meeting of the Ohio Section of the American Physical Society, ``Extragalactic Astrophysics and the New Era of X-ray Astronomy,'' Athens, OH, April, 2004
- Chandra X-ray Observatory Cycle 7 Peer Review, 2005
- referee for the Astrophysical Journal, the Astronomical Journal, Astronomy & Astrophysics, PPARC, NASA, ADS, etc.
