The IAEA Nuclear Security Series No. 37-G, Implementing Guide on Developing a National Framework for Managing the Response to Nuclear Security Events, was published in December 2019. This publication provides guidance to States on the development, implementation, and maintenance of a national framework for managing the response to nuclear security events. A national framework for managing the response to nuclear security events creates a structure and set of principles around which a State can frame its nuclear security response, addressing the interfaces which need to exist between responding agencies to ensure an effective, coordinated response. The Implementing Guide outlines relevant key issues which States should consider when developing, implementing and sustaining their national framework for responding to nuclear security events.