Leibman also won a Primetime Emmy Award in 1979 for his role as Martin 'Kaz' Kazinsky in his short-lived crime drama series Kaz.

Later in his career, he became widely known for his recurring role as Dr. Leonard Green on Friends (1996–2004), and for providing the voice of Ron Cadillac on Archer (2013–2016).

[4] Leibman made his film debut alongside George Segal in the dark comedy Where's Poppa?

)[citation needed] His other film appearances include Slaughterhouse-Five (1972), Your Three Minutes Are Up (1973) with Beau Bridges and Janet Margolin, Zorro, The Gay Blade (1981), Auto Focus (2002) and Garden State (2004).

[7] They also appeared together as husband and wife in the film Dummy (2003)[8][9] and in the TV series Law & Order in the episode "House Counsel" in 1995.

[10] Leibman received a 1993 Tony Award for his performance as Roy Cohn in the Pulitzer Prize-winning play Angels in America.