This concise volume provides essential advice and guidelines for all those medical personnel involved in the administration of radiation for diagnostic or therapeutic purposes. Legislation has been introduced in Europe and the UK to reduce patient radiation doses. In the UK, the Ionising Radiation (Protection of Patients Undergoing Medical Examination or Treatment) Regulations, known colloquially as the POPUMET Regulations, requires medical personnel to have received essential training in radiation protection. This volume covers the background material required by those taking approved training courses and summarises the core of knowledge which forms the basis of the POPUMET regulations. It will therefore be an essential textbook for all staff who are concerned with diagnostic radiology, nuclear medicine or radiotherapy and who are about to undertake this training.