From the autumn of 1911 to the summer of 1915, Arnold Schoenberg kept a diary--the only one known to exist--in which he recorded his experiences, feelings, and reflections. Despite its brevity, it is an extremely interesting document, as it provides us with a snapshot of his life in Berlin at a momentous time in his career, during which he composed Pierrot Lunaire. This volume also includes an introduction to the comic opera From Today to Tomorrow, which Schoenberg wrote during his time as a teacher at the Prussian Academy of Arts, where he succeeded Busoni as head of the master class in composition, and an essay in homage to the composer written by his pupil and close collaborator Josef Rufer.