- A. J. Gustin Priest papers, 1919/19764
- A. Jane Duncombe Architectural Papers, 1952/20023
- A. Patrick L. Prest, Jr. papers, 1941/201423
- A. Rufus Tonelson Papers, 1922/197513
- A. Willis Robertson Papers, 1921/1988, bulk 1946/19665
- A.B. Sharp, Compiler, Barr Family Genealogy, 1960/19691
- A.J. Morrison Collection, 1754/19751
- Abbye A. Gorin Architectural Collection, 1940/2006, bulk 1995/20062
- Abraham Anson papers, 1939/200570
- Academic Departments - Record Group 91
- Ackerly Family Papers3
- Ada Haldeman Ford, Suffragist, Papers, 1900/19701
- Adagio Press Collection, 1957/19937
- Adalbert J. Volck Collection of Etchings, 1861/19794
- Adam Empie Papers, 1811/2004, bulk 1811/18503