Recently, a great deal of literature on patron-driven acquisition (PDA) has been published that addresses the implementation and results of PDA programs at academic libraries. However, despite widespread worries that PDA will lead to unbalanced collections, little attention has been paid to whether patrons' and librarians' purchasing differ significantly. This study analyzes librarians' and PDA patrons' acquisitions at an academic library by relative collecting level and by subject (that is, Library of Congress class and subclass) to determine whether concern over patrons' collecting are warranted.