Instructor Rensselaer Polytechnic Institute, Troy, New York, 1957-1959. Patent engineer General Electric Company, Washington, 1959-1963. Senior patent attorney Atlantic Research Corporation, Alexandria, Virginia, 1963-1966.
Member firm Ryder, McAulay & Hefter, New York City, 1970-1973, Finnegan, Henderson, Farabow, Garrett & Dunner, LLP, Washington, since 1973. Professorial lecturer trademark law George Washington University, 1981-1990. Member advisory committee United States Patent and Trademark Office, 1988-1992, Trademark Review Commission, 1986-1989.
Board governors Brand Names Educational Foundation, 2001-2005. Member American Bar Association (chairman patent office affairs committee patent, trademark and copyright section 1976-1980, unfair competition committee 1980-1981, governing committee franchise forum 1994-1997), New York State Bar Association, District of Columbia Bar Association, Virginia Bar Association (director patent, trademark and copyright section 1976-1978), International Bar Association (chairman trademark committee 1986-1990), American Patent Law Association (chairman trademark committee 1979-1981, director 1981-1984), United States Trademark Association (director 1982-1984), Order of Coif, Alpha Epsilon Pi.