Proposing a stepwise, technology neutral approach and methodology for the development and adaption of regulatory safety requirements for the design of advanced nuclear power reactor technologies, this publication aims to support decision making by national regulatory authorities. It is based on integrated risk-informed, objective-oriented, performance-based approaches. A particular focus is placed on small and medium sized and modular reactor (SMR) designs. The publication identifies and exemplifies the key design features of SMRs to be considered important for the process of development or updating the regulatory safety requirements. The information presented is based on the experience provided by technical experts from Member States which have conducted the review of the adequacy of the set of regulatory requirements to the advanced nuclear power reactor technologies, and particularly for SMR designs.