Collection
- O'Shaughnessy Family Papers19
- O. D. Lambert Research Notes and Biographical Material on Stephen B. Elkins1
- O. Henry Collection1
- O.D. Linder, Compiler, Genealogy Records Regarding the Boyce, Dever, Gibson, and Linder Families1
- O.W. Riegel Papers2
- Oak Grove Baptist Church Records1
- Office of Admission records3
- Office of Alumni Engagement records1
- Office of Communications and Marketing subject files12
- Office of University Development records1
- Office of the Bursar Records7
- Office of the Dean of the School of Law - Record Group 81
- Office of the President Timothy J. Sullivan records1
- Office of the President, John Augustine Smith Records2
- Office of the President. James Blair Records1