The Group Theatre was a left-wing theater collective, formed in New York in 1931 by Harold Clurman, Cheryl Crawford and Lee Strasberg. It was intended to be a kind of breeding ground for actors, directors, and playwrights. The Group were pioneers of the method acting technique. The name "Group" came from the idea of the actors as a pure ensemble; there were to be no "stars." The company's first original play was the labor one-act Waiting for Lefty by Clifford Odets, produced in 1935.

The Group included Elia Kazan, Stella Adler, John Garfield, Luther Adler, Will Geer, Howard Da Silva , Franchot Tone, John Randolph, Joseph Bromberg , Michael Gordon , Paul Green , Clifford Odets, Paul Strand, Kurt Weill, Sanford Meisner and Lee J. Cobb.

In the ten years of its existence, the Group Theatre produced works by many important American playwrights. In the 1950s, most of the former members were called before the House Un-American Activities Committee (HUAC). Those who appeared as "friendly" witnesses, such as Elia Kazan, Clifford Odets, and Lee J. Cobb, avoided the fate of their colleagues who stood for their principles and, as a result, were blacklisted.