The fourth volume presents the main characteristics of the Bauhaus concept of the stage. It was essentially shaped by Oskar Schlemmer, who had taken over the stage department in 1923. Laszlo Moholy-Nagy took an interest in abstract kinetic and luminary phenomena which he examines in his essay Theatre, Circus, Variete. Farkas Molnar focused for his part on stage architecture, which he discusses in detail in this volume.