Who we are. American College of Radiology (ACR) is a progressive membership organization representing nearly 40,000 medical specialists in radiological care. As a member of our team, you will join a world leader in patient-centered care advocacy, policy and clinical research, quality and safety. Our culture encourages innovation, diversity, integrity and leadership. A nonprofit 501(c)(3), ACR (the American College of Radiology) has over 500 purpo...