The Laid-In collection was created in 2014 with the goal of documenting, preserving, and providing public access to items that accompany cataloged Special Collections materials but were not necessarily published with them. For instance, bookmarks, photographs, and other ephemera. These items are typically found during cataloging, at which time they are removed from the books and placed in this collection so that they are not lost. Additionally, the Laid-In collection houses documents that showcase the provenance of select cataloged items, such as correspondence with book dealers and donors.

If a cataloged item has associated laid-in materials, the catalog record will have a note describing the laid-in item and its box and folder location within this collection. The laid-in items are placed in folders labeled with the call number of the associated cataloged item.