In Establishments for medical diagnosis, treatment and research, widespread use is made of ionizing radiations from x-ray and other machines and from radionuclides. This report discusses the protection measures applicable to workers involved either directly or indirectly in such uses; in particular, it deals with the protection measures applicable to radiologists, radiation oncologists, nuclear medicine physicians, medical physicists, radiographers, scientists, technicians, radiopharmacists, engineers, nurses and others (such are cardiologists and orthopaedic surgeons), when their work involves exposure to radiation. This report is directed particularly towards the managing authority in each hospital or medical establishment and to the workers involved in work with radiation at such establishments. However, the report is also drawn to the attention of the relevant statutory authorities, whether national, regional or local, that are responsible for the enforcement of safety standards and for establishing training standards for workers.