Established in 1934, the American Board of Radiology (ABR) is an independent, not-for-profit professional association with headquarters in Tucson, Arizona. It oversees the certification and ongoing professional development of physician specialists in diagnostic radiology, interventional radiology, and radiation oncology, as well as medical physicists in diagnostic, nuclear, and therapy medical physics. The ABR certifies its diplomates through a comprehensive process involving educational requirements, professional peer evaluation, and examination.