Considerable progress has been made over the past several decades in the design and regulatory requirements for fire safety, in fire protection technology and in related analytical techniques. Substantial efforts have been undertaken worldwide to implement these advances in the interest of improving fire safety in both new and operating nuclear power plants (NPPs). This publication provides information and insights on lessons identified, and best practices to reflect the recent status of the worldwide nuclear power industry and to provide further detailed guidelines and assistance in enhancing the fire safety of operating NPPs.