Correspondence with Library staff, particularly Elizabeth Wrigley and Naomi Sawelson-Gorse, who was hired as Archivist in the 1980s. Much of the correspondence consists of research requests to the library, primarily about Duchamp, the Arensbergs and their circle of artist friends. There is also correspondence with the Philadelphia Museum of Art regarding the transfer of the art collection to the Museum. There are also many requests for photographs, photocopies, and permission to publish, as well as correspondence about research and loans for exhibits.