Playwrights on Playwriting. The Meaning and Making of Modern Drama from Ibsen to Ionesco. Edited by T. Cole. Introduction by John Gassner
Best American plays; sixth series, 1963-1967. Edited by John Gassner and Clive Barnes, with an introduction and prefaces to the plays by Clive Barnes
Play-Making. A Manual of Craftsmanship ... With a New Introduction to the Dover Edition by John Gassner
Twenty Best Plays of the Modern American Theatre. Edited with an Introduction by John Gassner. (Fifth Printing.).