Television offered consistently more work. Constantine appeared in anthology series of the late 50s, and in a 1961 episode of "The Untouchables". During the 1966-67 season, he played downtrodden tenant Jack Ellenhorn on "Hey, Landlord" (NBC), before winning the role of Seymour Kaufman on "Room 222," for which he won the 1970 Emmy Award as Best Supporting Actor in a Comedy Series. Constantine starred in "Sirota's Court" (NBC, 1976-77), playing a night court judge and had remained active as a guest player on shows like "Kojak" (as a Mafia don suffering from kidney disease) and several appearances on "Murder, She Wrote" in the 1980s.