The objective of this study is to better understand the process by which faculty members select the educational materials that they employ in their courses. The educational resource that people are most familiar with is the required textbook: faculty members select one or more books that all students are required to use through the duration of the course. Faculty also employ a wide range of other materials, some of which are supplemental or optional, and others that are required for all students. In addition to examining the overall resource selection process, this study also explores two particular classes of educational materials: those classified as open educational resources (OER) and a sub-set of OER known as open textbooks. The study also examines the extent to which faculty are aware of and/or adopting open textbooks. The survey results, using responses of over 3,000 U.S. faculty, show that OER is not a driving force in the selection of materials -- with the most significant barrier being the effort required to find and evaluate such materials. Use of open resources is low overall, but somewhat higher for large enrollment introductory-level courses. [For "Opening the Curriculum: Open Educational Resources in U.S. Higher Education, 2014," see ED572730.]