Cyril C. Thompson (1892-1976) had a long career in the accounting, management and public relations sides of the aviation industry, joining near the beginning of commercial aviation in 1928 and retiring just as the era of commercial jets began. Thompson was as an executive of United Air Lines for eighteen years, and later an airport planner, consultant, and prolific author and speaker. The papers of Cyril C. Thompson consist of a selection of items that he retained as mementos of the different stages of his career, plus materials and drafts for an unpublished biography of Idaho Senator William E. Borah and a never-completed personal history of United Air Lines on which he was working at the time of his death.