- Immediate past President of the American College of Environmental Lawyers
- Assistant Attorney General for the Environment and Natural Resources Division (ENRD) of the U.S. DOJ, 2015 - 2017
- ENRD Deputy Assistant Attorney General, 1995 - 2011
- ENRD Environmental Enforcement Section Chief, 1991-1995
- President of the Environmental Law Institute (2011-2014), a nationally recognized bipartisan organization known for its mission of making the law work for people, places, and the planet.
- The first government attorney elected President of the District of Columbia Bar, the largest bar in the nation
- The first government attorney selected as Chairman of the American Bar Association’s Section of Environment, Energy, and Natural Resources
- Past member of the Board of the National Conference of Bar Presidents, the D.C. Bar Foundation, the District of Columbia Bar Association, the Judicial Conference of the District of Columbia Circuit’s Standing Committee on Pro Bono Legal Services, and as a member of the Administrative Conference of the United States.