- Admiral John Randolph Tucker Papers, 1865/18971
- Advisory Committee Research Collection, 1772/20174
- Alexander Haight family collection, 1764/19761
- Alexandria History Collection (MS240), 1767/200812
- Alexandria Library Company Records (MS002), 1794/20074
- Allen Family Papers, 1766/19333
- Ancella Bickley, Historian, Research Papers regarding African-Americans, 1775/2018, bulk 1970/20111
- Anna Burton Ellett Collection, 1751/19321
- Anna Maria Hickman Otis Mead Chalmers family papers, 1821/18972
- Armistead-Cocke Papers, 1680/19172
- Arthur I. Boreman Papers, 1830/19491
- Atkeson-Morgan Family Papers, 1833/1923, bulk 1850/19002
- Austin-Twyman Papers, 1765/19393
- Bailey-Law Collection, 1825/19711
- Barker-Cooke Papers, 1809/1889, bulk 1848/18661