This study was performed to help answer questions surrounding the use of interlibrary loan data as a component in selecting periodicals to add to the subscription base of the Penrose Library at the University of Denver (Colorado). Few subscriptions were placed in this library in the 1980s that were not driven by interlibrary loan requests. If articles from a title were requested by three or more individuals, other than undergraduates, the title was considered a prime candidate for subscription. If the title was requested by four borrowers within a two-year period, it was reviewed for subscription, and requests from more than one academic department indicated an interdisciplinary interest in the title. In a nine-year time period, 126 periodicals were subscribed to as a result of this practice. Over 86% of these subscriptions survived a cancellation process. It is speculated that as libraries struggle to develop an effective mix of products to supply user demand, data supplied by interlibrary loan activity will be increasingly valuable in the periodical selection process. (MAS)