- A.B. Stickney, Compiler, Genealogical Materials, 1838/19591
- A.J. Morrison Collection, 1754/19751
- A.S. Hammack papers, 1864/19542
- Aaron Chipps, Coal Miner, Papers, 1912/19551
- Abbye A. Gorin Architectural Collection, 1940/2006, bulk 1995/20062
- Abner K. Pratt, II student papers, 19472
- Abraham Anson papers, 1939/200526
- Abraham Lincoln Collection, 1860/19651
- Academic Departments - Record Group 95
- Ackerly Family Papers13
- Ada Haldeman Ford, Suffragist, Papers, 1900/19701
- Adalbert J. Volck Collection of Etchings, 1861/19794
- Adam Empie Papers, 1811/2004, bulk 1811/18503
- Adams T. Rice papers, 1922/19604
- Addison H. Smith papers, 1917/1970, bulk 1917/19223