- A. Willis Robertson Papers, 1921/1988, bulk 1946/19661
- A.J. Morrison Collection, 1754/19751
- ALIVE (ALexandrians InVolved Ecumenically) Records (MS300), 1969/19951
- Abbye A. Gorin Architectural Collection, 1940/2006, bulk 1995/20061
- Abraham Anson papers, 1939/20052
- Adagio Press Collection, 1957/19931
- Adalbert J. Volck Collection of Etchings, 1861/19791
- Adam Empie Papers, 1811/2004, bulk 1811/18501
- Adele Blow Chatfield-Taylor family papers, 1899/19771
- Adele Goodman Clark papers, 1849/19781
- Administration records collection, 1776/19761
- Administrative Management Society records, 1941/1987, bulk 1941/19871
- Admiral Thomas J. Lopez Papers, 1973/20141
- Admissions Office student recruitment materials, 1950/20191
- Adolphus DeBussey, Soldier, Civil War Letters, 1861/1998, bulk 1861/18711