This publication has been developed to assist IAEA Member States in establishing and maintaining regulatory control through notification, authorization, inspection and enforcement in relation to facilities and activities with radiation sources, in order to achieve the fundamental safety and security objectives. The publication addresses the implementation of the requirements for safety and security in a harmonized way, taking into account differences in the requirements as well as differences in States' regulatory infrastructures. For example, in some States the same regulatory body is responsible for the control of safety and security, while in others, safety and security are controlled by separate regulatory bodies. A harmonized approach for notification, authorization, inspection and enforcement is intended to improve the efficiency and effectiveness of regulatory control through concurrent inspection for safety and security.