Ruben-Erik Diaz-Plaja is Head of the Policy Planning Unit in the Office of the Secretary General at NATO HQ in Brussels. He leads the team that contributes to developing, negotiating and implementing strategic policy priorities for the Secretary General, as well as leading work to strengthen strategic foresight within NATO. In this role, he has contributed to developing the 2024 review on NATO’s approach to the Southern neighbourhood;the 2022 Strategic Concept;the NATO 2030 agenda for the future of NATO;the 2021 Climate Change and Security Action Plan;and a comprehensive reform of the NATO Headquarters in 2018. Between 2012 and 2018, Ruben led work on NATO’s partnerships in the Political Affairs and Security Policy Division. Ruben has almost two decades’ experience working at the intersection of defence, security and democratic governance in the wider Euro-Atlantic region, including previous work with the OSCE in Warsaw, Poland, and Kosovo (2007-2012) helping to build democratic institutions in Eastern Europe/the Balkans. A Spanish/Dutch national, Ruben holds degrees in Politics (Edinburgh University, ‘04) and International Relations and Economics (Johns Hopkins University School of Advanced International Studies, ‘06).