- Alexander Haight family collection, 1764/197618
- Alexander Haight family collection, 1764/197713
- Alexander Hamilton, Jr. Letters, 1832/18331
- Alexander M. Davis Papers, 1850/18923
- Alexander McNutt Glasgow Family Papers, 1823/190314
- Alexander Sterrett Paxton Papers, 1858/1959, bulk 1861/18651
- Alexandria History Collection (MS240), 1767/20087
- Alexandria Scrapbook Collection (MS003), 1830/18932
- Allen Family Papers, 1766/193322
- Allen-Johnson Family Papers, 1838/19471
- Alumni Association Records, 1833/2014, bulk 1950/20051
- Amelia County, Va. Merchant's Account Book, 1852/1903, bulk 1852/18561
- American Civil War collection, 1860/18952
- Amos Koontz Papers II, 1865/19703
- Ancella Bickley, Historian, Research Papers regarding African-Americans, 1775/2018, bulk 1970/201129