The Report is intended for individuals and organizations responsible for calibrations and measurements of ionizing radiation. It is also expected to be of interest to agencies responsible for regulating radiological activities. The information and guidance provided should be useful to personnel making radiation measurements as well as to the users of calibration services. The report discusses methods for establishing and maintaining a measurement quality assurance program. The Report describes the methods that are necessary to manage the quality of ionizing-radiation measurements and calibrations. These methods are applicable to all types of radiation that are currently used in medical physics, radiation protection, industrial applications, and environmental measurements. The types of radiation covered include photons, electrons, neutrons, and charged particles. Quantities considered include absorbed dose, air kerma, fluence, and dose equivalent.