In 2014, the American Osteopathic Association, the American Association of Colleges of Osteopathic Medicine, and the Accreditation Council for Graduate Medical Education agreed to establish a new, single accreditation system for graduate medical education in the United States. This article focuses on recent policy enhancements and modifications to facilitate the transition to the single accreditation system and concludes with a discussion of the current transition planning after the end of the transition period on June 30, 2020.