In 2010, the Educational Commission for Foreign Medical Graduates (ECFMG, Philadelphia, Pennsylvania) announced that, beginning in 2023, graduation from a formally accredited medical school would be necessary for an international medical graduate (IMG) to be eligible for ECFMG certification. The announcement is notable because ECFMG certification is required for graduate medical training and practice in the United States. Graduating from a school accredited by an agency formally recognized by the World Federation for Medical Education (WFME), which has been formally evaluating and recognizing accrediting agencies since 2012, would fulfill the new ECFMG requirement. In 2015, ECFMG applicants came from 1,141 medical schools located in 139 countries or territories. As of December 2018, the WFME had formally recognized 14 accrediting agencies, which would cover only approximately a third of these recent ECFMG-certified IMGs. In this Perspective, the author compares the context of the ECFMG announcement to the beginning of accreditation in the United States so as to provide insight into the challenges the WFME faces as it seeks to evaluate and recognize what could ultimately be over 100 more accrediting authorities. The author then explores the possible effects of the requirement-specifically, its potential to restrict the ECFMG applicant pool-on the quantity and quality of the U.S. physician workforce. The author ends the Perspective by considering the implications of three broad policy options that the ECFMG could consider starting in 2023: implementation as announced, maintenance of the status quo, or a policy modified from the original announcement.