In addition to his directing career, he was drama critic for The New Republic (1948–1952) and The Nation (1953–1980), helping shape American theater by writing about it.

He was influenced especially by the work of Jacques Copeau and the Moscow Art Theatre, whose permanent company built a strong creative force.

He briefly studied Stanislavski's system under the tutelage of Richard Boleslavsky,[5] and became Jacques Copeau's translator/assistant on his production of The Brothers Karamazov, based on the novel by the Russian writer Fyodor Dostoevsky.

In November 1930, Clurman led weekly lectures, in which they talked about founding a permanent theatrical company to produce plays dealing with important modern social issues.

By building a permanent company, they expected to increase the synergy and trust among the members, who included Stella Adler, Morris Carnovsky, Phoebe Brand, Elia Kazan, Clifford Odets, and Sanford Meisner.

In the summer of 1931, the first members of the Group Theatre rehearsed for several weeks in the countryside of Nichols, Connecticut, at the Pine Brook Country Club.

Clurman was the scholar of the group — he knew multiple languages, read widely, and listened to a broad array of music.

In 1943 Clurman married Stella Adler, a charismatic theatre actress and later a renowned New York acting coach.

[9] Clurman had an active career as a director, over the decades leading more than 40 productions, and helping bring many new works to the stage.

[1] In addition, Clurman helped shape American theater by writing about it, as drama critic for The New Republic (1948–1952), The Nation (1953–1980), and New York (1968).

She summarized his approach as demanding the human being within the character: In 1947, I worked in a play under the direction of Harold Clurman.

[1] Ronald Rand brought Harold Clurman to life in his acclaimed solo play, LET IT BE ART!, which has been performed for 22 years in 26 countries, 20 U.S. states, and at the Theatre Olympics in New Delhi and Kerala.

[14] The Stella Adler and Harold Clurman Collection[15] came to the Harry Ransom Center at the University of Texas at Austin in 2003.

Among other noteworthy Clurman material are his correspondence (with Stella Adler and others), contracts and royalties, a diary, and theater programs he collected from 1926 to 1930.

[16] Clurman is a character in Names, Mark Kemble's play about former Group Theatre members' struggles with the House Un-American Activities Committee.