This document discusses open educational resources (OER). It defines OER as teaching, learning, and research materials that are free of cost, barriers to access, and carry open licenses allowing free use, adaptation, and sharing. OER can be retained, reused, revised, remixed, and redistributed under a Creative Commons license. Barriers to OER adoption include not enough subject resources, difficulty finding materials, and lack of comprehensive catalogs. OER can help lower student costs of textbooks and materials, improve retention and completion rates, and allow for ownership of course content and new collaborative opportunities. Librarians can play a key role in increasing OER awareness, education, adoption, and support services.