John Houchin explores the impact of censorship in twentieth-century American theatre, arguing that theatrical censorship coincided with significant challenges to religious, political and cultural systems. The study provides a summary of theatre censorship in the eighteenth and nineteenth centuries and analyzes key episodes from 1900 to 2000. These include attempts to censure Olga Nethersole for her production of Sappho in 1901 and the theatre riots of 1913 that greeted the Abbey Theatre’s production of Playboy of the Western World. Houchin explores the efforts to suppress plays in the 1920s that dealt with transgressive sexual material and investigates Congress’ politically motivated assaults on plays and actors during the 1930s and 1940s. He investigates the impact of racial violence, political assassinations and the Vietnam War on the trajectory of theatre in the 1960s and concludes by examining the response to gay activist plays such as Angels in America.