The majority of the collection relates to Paul R. Sweet's professional life, especially his service in the Research and Analysis (R and A) branch of the OSS during World War II. News clippings on Sweet's work, typescripts of his diaries, correspondence, declassified personnel files, and official reports and drafts Sweet authored or co-wrote for the OSS provide insights into the specifics of Sweet's work and the work of his colleagues. These documents also speak more broadly to the attitudes of the German population during the war. Many of the materials related to Sweet's OSS service are annotated with Sweet's commentary on the documents, written sometime after the war. Sweet's application for federal employment is also included.

To a lesser extent, the collection contains correspondence and Sweet's typewritten memoir from his tenure serving as U.S. Consul General in Stuttgart in the 1960s, as well as interviews he gave on his teaching career. Correspondence between Sweet and numerous friends and colleagues from the late 1970s-1990s is also included. Most of the correspondence pertains to Sweet's work as a historian and to German philosophy and history more generally, though Sweet's correspondence with several authors and historians details Sweet's service in the OSS.

The collection also contains materials that document Sweet's relationships with his family. These materials include correspondence from Paul R. Sweet to his brother and sister-in-law, JoAnne and William W. Sweet, Jr., and correspondence from historian William W. Sweet, son of Paul R. and Kathryn Sweet, to his parents and his sister and brother-in-law, Sarah and Gerald Rosen. In these letters, Paul and William Sweet comment on U.S. and world politics in the 1970s-1990s and give accounts of their personal lives. There are also a small number of photographs of the Sweets and their various homes.