In December, the USTUR mailed its 2023 Registrant newsletter to living Registrants and deceased Registrants’ next of kin. This year’s newsletter included a note from the USTUR’s director, as well as information about the USTUR’s special session at the Health Physics Society’s winter workshop on internal dosimetry; resumption of in-person advisory committee meetings and active inventory of historical NHRTR samples; and background information about the radium studies that were carried out by Argonne National Laboratory and other institutions.