Introduction: For the past decade, many educational institutions have launched initiatives to provide services and funding for professors to adopt, adapt, and create OER for enhancing student success. The initiatives could initially encourage faculty to use OER in their courses, but the continued effort to sustain proved difficult. Goal: The research goal is to explore how higher education institutions sustain OER initiatives by examining the experiences and perspectives of the key players: faculty, administrators, librarians, and instructional designers who work on the front line of OER initiatives as OER users, educators, and advocates. Methods: Exploratory two-case studies with qualitative methods including interviews, focus groups, and documents. Findings: The findings indicate that student success, people's ideology, and interest in OER are the driving forces behind OER initiatives. A combination of efforts was needed from grassroots and top-down to sustain the initiatives. Successful practices include a combination of institutional incentives and support, connecting key players, and implementing faculty outreach strategies. Themes are also identified for successes and challenges of sustaining initiatives. Successes include: (1) reducing costs for students; (2) helping faculty rethink courses and seek new ways of teaching; and (3) providing faculty freedom to customize for teaching as they desire. Challenges include: (1) experiencing difficulty in getting faculty on board; (2) needing a master database to increase OER discoverability; and (3) experiencing personnel turnover. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]