• Senior Fellow, Resources for the Future, 1993 - present.
• Director, Resources for the Future, Academic Programs, 1996 - present.
• Visiting Professor, Department of Economics, Johns Hopkins University, 1989 - 1995; 1999 - 2000.
• Fellow, Resources for the Future, 1983 - 1993.
• Founder and President, Companis, Inc., 1999.
• Visiting Professor, Princeton University, Woodrow Wilson School of Public Affairs, Fall Term 1996.
• Policy Analyst, Communications Satellite Corporation, 1979 - 1983.
• Junior Economist, U.S. Department of Commerce, Bureau of Economic Analysis, 1980.

• Federal Aviation Administration, Office of Associate Administrator for Commercial Space Transportation, Recognition for Outstanding Support in the Rulemaking on Licensing and Safety Requirements for Launch, 2006.
• U.S. National Aeronautics and Space Administration (NASA) Award, Contributions to U.S. Remote Sensing Industry, 2002.
• International Academy of Astronautics (elected to Full Membership), 2001.
• Top 25 "Rising Stars," National Space Society, 1994.
• Investment in People and Ideas Award, Resources for the Future, 1984.
• Institute for Professional Education Scholarship, 1982.
• Johns Hopkins University Fellowship, 1979 - 1983.

• "Commercial Space." Delivered to the U.S. House of Representatives, Subcommittee on Space and Aviation, April 20, 2005.
• "Advantages and Disadvantages of Prizes in a Portfolio of Financial Incentives for Space Activities." Delivered to the U.S. House of Representatives, Committee on Science, July 15, 2004.
• "An Economics View of Satellite Solar Power." Prepared for the U.S. House of Representatives, Committee on Science, Subcommittee on Space and Aeronautics, September 7, 2000 (delivered by John S. Fini).
• "Commercializing Space." Delivered to the U.S. House of Representatives, Committee of Science, Subcommittee on Space and Aeronautics, July 18, 2000.
• "The Commercial Space Act of 1997: Commercial Remote Sensing." Delivered to the U.S. House of Representatives, Committee on Science, Subcommittee on Space and Aeronautics, May 21, 1997.
• "The Omnibus Space Commercialization Act of 1996 and the Space Business Incentives Act. H.R.1953." Delivered to the U.S. House of Representative, Committee on Science, March 5, 1996.

Appointments:

• Advisory Committee for the 1988 ITU World Administrative Radio Conference, Federal Communications Commission
• Panels convened by the Committee on Science and Technology of the U.S. House of Representatives and the American Institute of Aeronautics and Astronautics
• Organizing Committee for 1988 and 1989 of the Annual Telecommunications Policy Research Conference; Chair, 1989-1990
• Review panel, NASA Remote Sensing Commercialization Research Announcement
• Panels by the Space Studies Board, National Research Council
• Task Force on Priorities in Space Research, Space Studies Board, National Research Council
• Review panel, Congressional Budget Office, Spectrum Management Workshop
• Advisory panel, Earth Observations Project, U.S. Congress, Office of Technology Assessment
• Ad Hoc Group on Data Exchange and Charging, American Meteorological Society
• Subcommittee on Space Debris, International Astronomical Association
• Planning Committee, National Meeting, American Astronautical Society
• Space for America Committee, American Astronautical Society
• Space Activities and Society Committee, International Academy of Astronautics
• Study Group, John Heinz III Center for Science, Economics, and the Environment
• Chair, Congressionally mandated "Economic Study of Space Solar Power"
• NASA Space Science Advisory Committee
• NASA Space Science Outreach and Public Education Committee
• National Research Council, Board on Physics and Astronomy, Helium Reserve Committee
• National Research Council, Space Studies Board, Steering Group on Space Applications and Commercialization
• National Research Council, Aeronautics and Space Engineering Board, Committee for Independent Assessment of the NASA Investment Strategy in Space Solar Power
• National Research Council, Review of a Technology Assessment on Concentrating Solar Power Energy Systems
• National Research Council, Aeronautics and Space Engineering Board, Steering Committee for Workshops on Human and Robotic Exploration and Development of Space
• National Research Council, Space Studies Board, Workshop Study on Earth Observations and Applications from Space: A Community Assessment and Strategy for the Future
• National Research Council. Aeronautics and Space Engineering Board, Member
• National Research Council, Space Studies Board, Review Team for Science Roadmaps for the National Aeronautics and Space Administration
• US Department of Homeland Security, Senior Advisory Group on the Interagency Modeling and Atmospheric Assessment Center (IMAAC)

Panels and Symposiums:

Co-organizer and contributor, "Explorations in Space Policy," a symposium sponsored by Resources for the Future and the National Academy of Engineering, Washington, D.C., June 1986.

Special Projects:
Spearheaded joint effort of the Mount Vernon Association and Women in Aerospace for U.S. space shuttle flight of replica flag flown by George Washington during the Revolutionary War; flag now on display at Mount Vernon, October 1998.