The implementation of the women, peace and security resolutions of the United Nations Security Council (UNSC) faces ongoing challenges. National action plans (NAPs) have been developed as a means to address the implementation gap, with 40 such NAPs developed by UN member states to date. NAPs aim to enable states’ commitments under the various UNSC resolutions to become the actions they take in both domestic and foreign policy. Stand-alone NAPs offer significant opportunity to advance the national implementation of the women, peace and security (WPS) agenda. They also present risks, however, most notably in terms of how strategic provisions of the various WPS resolutions are translated into actions in an action plan. Successful implementation of the WPS agenda is thus not just contingent on the adoption of an NAP, but the proper implementation of that NAP. This policy brief provides an overview of the key opportunities and constraints presented by NAPs and the action planning process itself, and concludes with a range of recommendations for enhancing the development and implementation of NAPs for the overall fulfilment of the WPS agenda.