Somewhere in the basement of the Bulfinch Building, Dr. Hertz carried out experiments with results that would forever change medicine. What began as an investigation into thyroid disorders widened into an entirely new field: nuclear medicine,” said David F.M. Brown, MD, Mass General President, during an Oct. 8, 2021 landmark dedication ceremony at Mass General. “Today, more than 10 million patients in the United States are treated each year with radioisotopes of various kinds. We are proud that the Mass General was the site of such a significant medical milestone, and we thank the American Chemical Society (ACS) for this extraordinary tribute to a pioneer in medicine.” Additional speakers paid tribute to Hertz were his daughter Barbara Hertz; Katherine Lee, PhD, of the ACS Board of Directors; Sumner Fanger, a close friend of Hertz; and Anna Sromek, PhD, past chair of the Northeastern section of the ACS. The ACS established the National Historic Chemical Landmarks Program in 1992 to enhance public appreciation for the contributions of the chemical sciences to modern life in the nation and to encourage a sense of pride in their practitioners.