Addressed to all people of theatre, this book includes the fundamental research, based on Sergei Tcherkasski's doctoral dissertation, on the directing and teaching of Richard Boleslavsky (1889-1937) and Lee Strasberg (1901-1982) as a development of the Stanislavsky System. The author closely scrutinizes documents of the life and work of the Moscow Art Theatre and its First Studio that became a cradle for the most important discoveries of Stanislavsky into actor training in the 1900s and 1910s. The book continues with exploration of the artistic creation and training methodology of the American Laboratory Theatre (1923-1930), the Group Theatre (1931-1940) and the Actors Studio (since 1947). Sergei Tcherkasski looks at history of American and Russian theatre of the 20th century, raises fundamental questions on the art of acting and actor training and provides specific exercises from the practice of Stanislavsky, Boleslavsky and Strasberg.