Vindicated by Its Critics: The Kent Study in Light of Other Research on Library Circulation

In 1979, a study at the University of Pittsburgh Library found that 40% of the books added in the previous six years had not circulated. 37 years later, we librarians still cite that number and many of us use it (among other factors) to justify moving in the direction of patron-driven acquisition. A critic of that practice argues that many subsequent circulation studies contradict the Kent Study. But do they?