Beyond the Horizon: Broadening Our Understanding of OER Efficacy is a concise yet comprehensive resource designed to provide insight into the current state of research and reporting on Open Educational Resources (OER) efficacy. This guide explores existing frameworks, delves into key themes and gaps, and highlights emerging opportunities in the realm of OER efficacy. In addition to offering an overview of OER efficacy research and reporting, this guide motivates you to: - Evaluate how to measure the impact of OER within your own educational institution. - Discover effective strategies for sharing the impact of OER with the wider open education community or other key stakeholders. - Gain an understanding of various OER efficacy models implemented across different global regions. - Find inspiration to envision and implement long-term OER initiatives that can bring lasting benefits to your educational community. Identify and address the challenges and opportunities associated with the adoption and usage of OER.