In 1927 Brecht became part of the "dramaturgical collective" of Erwin Piscator's first company, which was designed to tackle the problem of finding new plays for its "epic, political, confrontational, documentary theatre". Brecht collaborated with Piscator during the period of the latter's landmark productions, Hoppla, We're Alive! by Toller, Rasputin, The Adventures of the Good Soldier Schweik, and Konjunktur by Lania. Brecht's most significant contribution was to the adaptation of the unfinished episodic comic novel Schweik, which he later described as a "montage from the novel". The Piscator productions influenced Brecht's ideas about staging and design, and alerted him to the radical potentials offered to the "epic" playwright by the development of stage technology (particularly projections). What Brecht took from Piscator "is fairly plain, and he acknowledged it" Willett suggests:
1927 also saw the first collaboration between Brecht and the young composer Kurt Weill. Together they began to develop Brecht's Mahagonny project, along thematic lines of the biblical Cities of the Plain but rendered in terms of the Neue Sachlichkeit's Amerikanismus, which had informed Brecht's previous work. They produced The Little Mahagonny for a music festival in July, as what Weill called a "stylistic exercise" in preparation for the large-scale piece. From that point on Caspar Neher became an integral part of the collaborative effort, with words, music and visuals conceived in relation to one another from the start. The model for their mutual articulation lay in Brecht's newly formulated principle of the "separation of the elements", which he first outlined in "The Modern Theatre Is the Epic Theatre" (1930). The principle, a variety of montage, proposed by-passing the "great struggle for supremacy between words, music and production" as Brecht put it, by showing each as self-contained, independent works of art that adopt attitudes towards one another.