State Bar of California (admitted to practice, 1978)

Bar of the United States Court of Appeals for the District of Columbia Circuit (admitted to practice, 1979)

American Bar Association (Chairman, International Communications Committee, 1992-1995, and Co-Chairman, International Legal Education Committee, 1995 -, Section of International Law and Practice; Member, Sections of Administrative Law and Regulatory Practice; Antitrust Law; Public Utility, Communications and Transportation Law; Science and Technology; Forums on Communications Law and the Entertainment and Sports Industries)

Federal Communications Bar Association (Member, Law Journal and Interactive Media Practice Committees)

Editorial Advisory Board, BNA's Electronic Information Policy & Law Report (1995- )

Contributing Editor, Cable Communications Magazine (1983-95)

Editorial Advisory Board, Eurowatch: Economics, Policy and Law in the New Europe (1992- )

Editorial Advisory Board, Federal Communications Law Journal (1980-84, 1988-94)

Editorial Advisory Board, High Technology Law Journal (1986-88)

Editorial Advisory Board, International Journal of Communications Law and Policy (1999- )