- Associate Covington & Burling, Washington, 1964-1973, partner, 1973—2007, general counsel, since 2005, senior counsel, since 2007. Adjunct faculty University Virginia Law School, 1968-1986, American University 1988-1992. Lecturer in field.
- Bar: District of Columbia 1965, United States Court Appeals (District of Columbia circuit) 1965, United States Court Appeals (6th circuit) 1966, Supreme Court of the United States Court 1971, United States Court Appeals (9th circuit) 1975, United States Court 2nd District Court of Appea circuit) 1980, United States Court Appeals (4th circuit) 1980, United States Court Appeals (3d circuit) 1981, United States Court Appeals (federal circuit) 1982, United States District Court Maryland 1992, United States Court Appeals (11th circuit) 2000.
Fellow American Bar Foundation. Member American Bar Association (litigation and antitrust sections), District of Columbia Bar Association (past chairman legal ethics committee, special committee legal specialization, member steering committee section courts, lawyers and administration justice, District of Columbia rules professional committee, committee on interdisciplinary practice, Certified Appreciation 1987, 2002), Phi Beta Kappa.