 Greenaway worked in private practice in New York City from 1981 until 1985.He became an Assistant United States Attorney at the U.S. Attorney's Office for the District of New Jersey from 1985 until 1989, when he became the chief of narcotics for the District of New Jersey.From 1990 until 1996, Greenaway worked as in-house counsel for Johnson & Johnson in New Brunswick, New Jersey.