The Thomas S. Cullen Collection covers his career at Johns Hopkins. It also includes material related to Cullen's father. Series include correspondence, manuscripts, addresses, illustrative materials, memorabilia, and reprints. The manuscripts primarily pertain to gynecological subjects, with titles such as "Myoma of the Uterus," "Cancer of the Uterus," and "Gynecology of Yesterday and Today." Along with the Howard Kelly Collection, the Cullen papers provide a comprehensive view of the department of gynecology at Johns Hopkins during its formative years.