The Rosenbach Fellowship in Bibliography, established by the Trustees of the University of Pennsylvania in 1928, honors a gift for that purpose from A.S.W. Rosenbach, one of America's greatest book dealers and collectors. Its intention is to further scholarship and scholarly publication in bibliography and book history, broadly understood. Rosenbach Fellows typically present a series of three lectures over a period of one to two weeks while in residence at the University of Pennsylvania. 

The Rosenbach Lectures are the longest continuing series of bibliographical lectureships in the United States. The series began in 1931, with Christopher Morley as the first Rosenbach Fellow. Over the years, lecture topics have included fifteenth-century printing, the relationships between print and manuscript, papermaking, book illustration, American reading and publishing, and medical and scientific texts. Most recently, William Zachs, independent scholar and book collector lectured on the broad question "What can we learn from looking at multiple copies of a book?" His three lectures were organized around a series of case studies - mainly from 18thh-century - books that are either a part of or relate in some way to his own collection. Each case study illustrates different bibliographical and/or book-historical issues that cannot be fully understood from the examination of a single copy.