This Safety Report provides detailed information on ageing management programmes and time limited ageing analyses to manage existing and potential ageing effects and degradation mechanisms of structures, systems and components (SSCs) that are important to the safety of nuclear power plants. It has been written to assist operating organizations and regulatory bodies by specifying a technical basis and providing practical guidance on managing ageing of mechanical and electrical instrumentation and control components, and civil structures. It also provides a common, internationally recognized basis of what constitutes an effective ageing management programme, a knowledge base on ageing management for design of new plants and design reviews, and a roadmap to available information on ageing management.