The collection includes Personal (Series I) and Professional Papers (Series II) of chemist and science fiction writer John D. Clark, dating from 1923-1988. Series I: Personal Papers includes various awards and certificates, photographs, diaries from 1924-1984, student papers, articles written by his father, and correspondence from his mother. There is an additional autobiographical manuscript in in Series II written by John A. Clark called "Reminiscences."

Series II: Professional Papers contains correspondence between colleagues and contemporaries, reports, and Clark's science fiction and non-fiction writing. This includes a manuscript of Ignition!, articles on and by John D. Clark, and various shorter pieces of work. It also contains photographs and a large "proclamation" saluting Clark's work, signed by various colleagues.