- A New Map of North America (Reproduction), 19791
- A. Christian Compton Papers, 1960/19991
- A. E. Dick Howard papers, 1928/201714
- A. H. Hand Papers, 1835/20092
- A. J. Davis Family Collection, 1874/2007, bulk 1874/19071
- A. Jane Duncombe Architectural Papers, 1952/20023
- A. Patrick L. Prest, Jr. papers, 1941/201425
- A. Willis Robertson Papers, 1921/1988, bulk 1946/19663
- ALIVE (ALexandrians InVolved Ecumenically) Records (MS300), 1969/199510
- Abbye A. Gorin Architectural Collection, 1940/2006, bulk 1995/20062
- Abraham Anson papers, 1939/200536
- Academic Affairs: Academic Program Reviews, 1976/2018, bulk 1992/20181
- Academic Departments - Record Group 92
- Ackerly Family Papers2
- Adagio Press Collection, 1957/19936