The library literature on collection development has recently seen a spate of publications and presentations on patron-driven acquisitions (PDA). The bulk of this literature has addressed the implementation and touted the successes of PDA at academic libraries, yet a counter literature has been developing, much of it addressing the potential failings of library patrons as selectors. There has been little focus, however, on patrons' potentially problematic behaviors as post-purchase users of PDA materials. This study aimed to discover whether library patrons might in effect be monopolizing print books purchased via PDA via circulation renewals. The study found that there was a statistically significant difference in the proportions of circulated and circulated-and-renewed books acquired via PDA, librarians' orders, and approval plan selection. The study also found that ratios of renewals to circulations for circulated-and-renewed approval plan books were significantly greater than were the ratios for librarians' and PDA books, generally, and for books available for more than one year but less than six years. There were no significant differences for books available for one year or less. PDA books' renewal-to-circulation ratios were significantly greater than those of approval plan books only for books that had circulated a single time. KEYWORDS: patron-driven acquisition, collection use, print books, academic libraries, patron behaviors, INTRODUCTION It has been variously referred to in the library literature devoted to collection development as books on demand, buy not borrow, collaborative collection development, demand-driven acquisitions, direct purchase, just-in-time [...]