Consists of correspondence, reports, printed material, and memorabilia, including certificates, plaques, and photographs. The collection includes material generated by Herschel W. Nisonger (predecessor), William Dowling (successor), and Andrew Hendrickson during their tenures as professors of adult education at Ohio State University, however the bulk of the material belongs to Hendrickson (1947-1967). Correspondents whose letters are of significant depth and duration include: William D. Dowling, John B. Holden, Cyril O. Houle, Glenn S. Jensen, Homer Kempfer, Malcolm S. Knowles, Burton W. Kreitlow, Fern Long, Robert A. Luke, Herschel W. Nisonger, Newton C. Rochte, and Coolie Verner. Part 2, added in 1991, contains miscellaneous pamphlets, additional memorabilia, and some material relating to the Adult Education Association (AEA), the National Association of Public School Adult Educators (NAPSAE), and the National Education Association (NEA).