The University Librarian series contains the records of the various individuals who have held the position and provide an overview of the Library's historical development from the vantage point of one of the few roles that have remained relatively static throughout the Library's entire existence. As the chief administrator of the Library, the University Librarian is involved to some extent in nearly every aspect of the institution's planning and evolution. This is especially true in the earlier years of the Library when activities later undertaken by separate departments were somewhat more centralized around the Librarian. Such diversity of purpose is represented in the University Librarian records themselves, which primarily contain correspondence, subject files, and other documentation relating to topics as varied as collection development, finances, fundraising, organizational and staff matters, and university policy. Please see subseries descriptions for further information regarding the individual subseries.

The Library Offices and Departments series documents the work and operations of some of the major offices and departments within the Library. Materials include correspondence, reports and statistics, meeting records, policy and procedure manuals, and budgets. Owing to various administrative shifts over time as well as to the nature of the tasks overseen by some of the offices and departments, the records in this series occasionally overlap with those found elsewhere in the Library Records. Please see individual subseries descriptions for further information.

This series contains the records of the Princeton University Library's Department of Rare Books and Special Collections. First organized in 1948-49, the Department has oversight of the Library's holdings of rare books, manuscripts, graphic arts, and numismatics, as well as several other special collections such as the University Archives, the Public Policy papers, and the Cotsen Children's Library. The origins of the Department of Rare Books and Special Collections extend nearly to the beginning of the Library, and much of this material predates the official formation of RBSC as a unit. Other records concerning the early Department of Rare Books and Special Collections can be found in Subseries 1D: Julian Parks Boyd. Please see subseries descriptions for further information regarding the individual subseries.

The Catalogues and Technical Records series consists of records in a variety of forms which convey the growth and management of the Library's main collection. The records in this series demonstrate not only the continual growth to the Library's holdings, but also developments in methods of cataloging, classifying, and shelving the collections.

The Friends of the Princeton University Library series consists of material that documents administrative activities of the organization and records the many events that it conducted on behalf of the library. Please see subseries descriptions for further information regarding individual subseries.