The papers of Allen Janssen span the years 1926 to 1980, with the bulk of the material covering the year 1940 to 1972. included are examinations given to professional engineers seeking registration in Idaho, outlines and exams for courses he taught at the university and other material concerning the engineering college, materials relating to his work in a military construction battalion, and papers and newspaper clippings dealing with organizations he was involved with such as Pacific Consultants, which includes reports done for the Public Land Law Review Commission; Bonneville Power Administration; Moscow Chamber of Commerce, especially the Transportation Committee; and the Civil Defense Executive Reserve.