At the University of Arizona, we're frequently asked how the Libraries and campus-owned BookStores collaborate effectively on OER initiatives and other textbook cost-reduction projects. Cheryl Cuillier, the UA Libraries' OER Coordinator, and Cindy Hawk, Assistant Director of the UA BookStores, will share the secrets of our success, which can be replicated at other institutions. In this session, we'll cover data sharing, joint presentations to campus, our campus-wide OER Action Committee, how we've leveraged the Faculty Senate and Provost's involvement, how we notify students of free textbooks on the BookStores' website, and other strategies.