- A. Willis Robertson Papers, 1921/1988, bulk 1946/1966191
- A.B. Stickney, Compiler, Genealogical Materials, 1838/19591
- A.H. Forman, Collector, Records regarding Chesapeake and Potomac Telephone Company, 1936/19381
- A.J. Morrison Collection, 1754/19751
- A.S. Hammack papers, 1864/19542
- Aaron Chipps, Coal Miner, Papers, 1912/19551
- Abbot E. Smith Papers, 1930/19393
- Abraham Anson papers, 1939/20052
- Abraham Johnson Family Genealogy, 1930/19391
- Abraham Lincoln Collection, 1860/19651
- Academic Departments - Record Group 99
- Ackerly Family Papers21
- Ada Haldeman Ford, Suffragist, Papers, 1900/19701
- Adalbert J. Volck Collection of Etchings, 1861/19794
- Adam Empie Papers, 1811/2004, bulk 1811/18503