After graduating from the College of William & Mary in 1953, Leach went on to earn both a master's degree and a doctorate from the University of Illinois.
After moving to New York City, Leach became the artistic director of La MaMa Experimental Theatre Club for much of the 1970s.
Leach's additional theatre directing credits include two projects that originated at the Public and then transferred to Broadway: The Human Comedy (1984) and The Mystery of Edwin Drood (1986), for which he won his second Tony Award.
[11] While teaching at Sarah Lawrence, Leach met then-students Brian De Palma and Cynthia Munroe.
He also directed the films All's Well That Ends Well (1978) with Frances Conroy for television[12] and a straight-to-video version of Coriolanus (1979) with Denzel Washington and Morgan Freeman.