Oakley served as Librarian of the Madison Public Library from 1884 to 1889 before going to work for the State Historical Society Library. Oakley was one of the founders of the Wisconsin Library Association in 1891. She was one of two librarians from Wisconsin who joined the American Library Association in 1886 (only the second and third to do so) when ALA met in Milwaukee. Oakley became Cataloger and Assistant Librarian at the State Historical Society where she worked for 19 years. She served as Secretary-Treasurer of the National Association of State Libraries. She later became Cataloger for the Seattle Public Library and Supervisor of Branches for the Los Angeles Public Libraries.