Most countries in the world use the SI (Syst?me International, also known as the metric system) units for radiation measurements in commercial and technical activities. The United States, in contrast, uses a mix of SI and conventional units for radiation measurements, despite 30-year-old national and international recommendations to exclusively use SI. Radiation professionals in the United States are faced with the need to understand both systems and make conversions between the two. In September 2016, the National Academies of Sciences, Engineering, and Medicine organized a workshop to explore potential communication improvements associated with adopting the international system of units (SI units) for radiation measurements in the United States. Participants discussed potential improvements in the effectiveness of responding to national and international radiation emergencies, international experiences in adopting the exclusive use of SI units of radiation measurements, and steps needed to adopt the exclusive use of SI units in the US in terms of timing, implementation, and ways to overcome or manage technical, economic, and policy barriers. This publication summarizes the presentations and discussions from the workshop. Table of Contents Front Matter Overarching Workshop Themes 1 Introduction and Context 2 Practices in Use of Units for Radiation Measurements 3 Exclusive Use of SI Units for Radiation Measurements 4 Lessons Learned from International Experiences 5 Possible Steps Toward the Exclusive Use of SI Units for Radiation Measurements References Appendix A: Workshop Agenda Appendix B: Speaker Biographies Appendix C: Planning Committee Member Biographies