Frederick G. Kilgour was one of the 20th century's most illuminating and influential librarians. He changed librarianship by starting OCLC, Inc. and by creating the WorldCat bibliographic database, now the world's largest. In seven of his last eight published, scholarly works, Kilgour reported on experiments he and his co-authors conducted that discovered a way to further reduce cataloging costs by setting up a simple discovery system for known-item searches. This book examines Kilgour's last eight papers in the context of his contributions as a librarian and within the framework of contemporary information discovery systems.