- A. Patrick L. Prest, Jr. papers, 1941/201420
- A. Rufus Tonelson Papers, 1922/197517
- A. S. Lara papers, 1856/18611
- A. Willis Robertson Papers, 1921/1988, bulk 1946/19661,192
- A.B. Stickney, Compiler, Genealogical Materials, 1838/19591
- A.E.S. Stephens Papers, 1949/19619
- A.J. Morrison Collection, 1754/19751
- Abbye A. Gorin Architectural Collection, 1940/2006, bulk 1995/20062
- Abraham Anson papers, 1939/200527
- Abraham Lincoln Collection, 1860/19651
- Academic Departments - Record Group 92
- Ackerly Family Papers12
- Ada Haldeman Ford, Suffragist, Papers, 1900/19701
- Adagio Press Collection, 1957/19932
- Adalbert J. Volck Collection of Etchings, 1861/19794