- IAWA: International Archive of Women in Architecture Records1
- Independent Order of Odd Fellows, Sylvan R.D. Lodge No. 220 (Alba, Mi.), Minute Book2
- Independent Order of St. Luke Records3
- Inge Horton Architectural Collection65
- Institute for the History of Technology and Industrial Archaeology Records20
- International Association for Identification Records32
- International Order of Odd Fellows, Lodge 134, Ledgers1
- Ira E. Robinson Papers2
- Iron Gate, Virginia, Ledgers,1
- Irvine-Saunders Family Papers
1745-1910 Inclusive12
- Isaac & Josiah Williams Brick Company, Account Books1
- Isaac B. Smith, Farmer and Music Teacher, Newspaper Clippings and Other Material1
- Isaac McNeel (b.1830) Papers1
- Isaac White Letters2
- Isabella Bain memory album1