Ron Leibman is an American actor, best known for playing ‘Dr. Leonard Green‘ in the TV sitcom ‘Friends’ (1994-2003). He also played Martin 'Kaz' Kazinsky’ in the crime drama series ‘Kaz,’ from 1978 to 1979. He earned a ‘Primetime Emmy Award’ for his role in the series. He also won the ‘Tony Award’ for his performance as ‘Roy Cohn’ in the play ‘Angels in America’ (1993). He made his screen debut as ‘Johnny’ in the TV series ‘The Edge of the Night’ (1956). He made his film debut in ‘Where's Poppa?’ (1970). Some of his successful films include ‘The Super Cops’ (1974), ‘Norma Rae’ (1979), ‘Phar Lap’ (1984), ‘Door to Door’ (1984), ‘Auto Focus’ (2002), and ‘Garden State’ (2004). He also starred in a few unsuccessful films, such as ‘Romantic Comedy’ (1983) and ‘A Little Help’ (2010). He appeared in TV series, such as ‘Murder, She Wrote’ (1990-92), ‘The Sopranos’ (2006), and ‘Archer’ (2013-16), in a voice role.