This series contains the personal materials of Otto Duke, including personal research and reading, political papers and diagrams, personal photos, sheets from a pocket notebook, invitations, business cards, name tags, travel information, newspapers (Utah, Alaska, Oklahoma), pamphlets, and miscellaneous other materials. They are dated from 1920 to 1975.

Otto Duke was secretary-treasurer of the Intermountain Alumni Association of the Theta Tau fraternity. This series deals with that association and includes correspondence, monthly luncheon attendance, "The Gear of Theta Tau," receipts, 40th anniversary meeting planning, "Balfour Blue Book," and minutes of biennial Theta Tau conventions. Dates range from 1955 to 1969.