Certification is potentially available to M.D. and D.O. emergency physicians who have successfully completed an ACGME-approved or AOA-approved residency in emergency medicine, completed a year of practice, and passed written and oral exams. At one time, ABEM offered certification eligibility via a practice track, allowing training in another specialty, practicing emergency medicine, and then passing the ABEM exam. Currently, approximately one third of the emergency physicians currently holding ABEM certification were "grandfathered" in to certification eligibility via the practice track.