The protection of people, society and the environment from the harmful effects of ionizing radiation is at the heart of the Department for Nuclear Safety and Security’s work. Whether the cause is an unsafe act or a security breach, it aims at providing a strong, sustainable and visible global nuclear safety and security framework. The International Atomic Energy Agency’s (IAEA’s) Department of Nuclear Safety and Security offers several peer review and advisory services in the various domains of nuclear safety and security. These services play key roles for global nuclear safety and security, enabling countries to benefit from the independent insights of leading international experts, based on the common reference frame of the IAEA safety standards and security guidance. The IAEA’s Department of Nuclear Safety and Security offers 19 different services, all conducted only at the request of a Member State. Each of these services is undertaken by a team of international experts whose conclusions and recommendations are compiled in a report which advises the Member State on ways of improving its nuclear safety and security. A follow-up mission assesses progress made in implementing the recommendations.