Primarily correspondence and writings documenting Arnheim's teaching career and his professional interest in art and psychology. Writings include diaries, twenty-five volumes, including travel diaries, and two volumes in German while an educator in Berlin and during his travels to Rome and England (1919-1922 and 1934-1938). Correspondence, 1959-1982, with German publishers and editors, 1960-1979; Dumont Buchverlag, 1963-1980, Carl Hanser Varlag, 1974-1981, Helmut Diederich, 1974-1981, Franz Rudolf Knubel, 1971-1981, Werner Korbs, 1976-1982, Jurgen Weber, 1972-1981, and others. Biographical material; bibliography of writings; legal papers; files of correspondence, some arranged chronologically, but most alphabetically by subject; diaries, 1919-1987; lecture notes; and writings, including manuscripts, articles, book reviews, published articles. Manuscripts include: "Art & Visual Perception," "Art of Seeing," "Autobiography of a Work of Art: Picasso's Guernica," "Depth Effect of 2D Figures," "Disorder & Entropy, Order and Art," "Dynamics of Architectural Form," "New Essays on the Psychology of Art," "Photographing Michelangelo," and a work of fiction "The World Upside Down" (Verkehrte Welt). Also included are printed material (book notices, book reviews, interviews, clippings) and audio tapes (untranscribed) of lectures and interviews. Among the subject/correspondence file titles are: American Society for Aesthetics, Architects, Art Historians/Critics, Dance, Film, Harvard University, Japan/Fulbright Trip, University of Michigan, Museum of Modern Art, Music, New School of Social Research, Psychiatrists, and Television. Correspondents include Josef Albers, Gordon Allport, Joseph Campbell, Gyorgy Kepes, Hans Richter, Alice Sheldon, and B.F. Skinner.