The year was 1922. The Lincoln Memorial was dedicated on May 30. A first-class postage stamp cost two cents. Insulin was the revolutionary new treatment for diabetes.

And Sister M. Beatrice Merrigan took her Radiography Exam on Nov. 17. The test included 20 essay questions and a prescribed set of radiographs. She was notified of her certification the day after Christmas, when she earned the distinction of becoming the country’s first Registered Technologist.

We were the Registry—founded earlier that year by the Radiological Society of North America, with the support of the American Roentgen Ray Society and the American Society of X-Ray Technicians.

The Registry was incorporated in 1936 as the American Registry of X-Ray Technicians. Its board was appointed by the Radiological Society of North America and the American Society of X-Ray Technicians. By the end of the decade, there would be more than 2,400 Registered Technologists.

In 1944, the American College of Radiology assumed the responsibility of appointing board members along with the American Society of Radiologic Technologists.

Forty years after its founding, the Registry expanded its program of examination and certification by adding exams in Nuclear Medicine Technology and Radiation Therapy. At that time, the organization’s name changed to The American Registry of Radiologic Technologists, a name more inclusive of all three disciplines of certification. By the end of the 1960s, ARRT would boast a total of 56,000 certificates—some 700 in Nuclear Medicine Technology and nearly 300 in Radiation Therapy.

The decade of the '90s saw a sweeping expansion of ARRT’s offerings. The new postprimary pathway was launched with certification in Cardiovascular-Interventional Technology and Mammography. New disciplines were added as technology emerged. As the millennium ended, ARRT had converted all of its exams from paper-and-pencil to computer-based testing.

In November 2022, ARRT marked a century of recognizing qualified people who work in medical imaging, interventional procedures, and radiation therapy. Today we certify and register more than 345,000 technologists in 15 disciplines.