Diplomacy, Development, and Defense (3Ds) – as represented by the Department of State (State), the United States Agency for International Development (USAID), and the Department of Defense (DoD or Defense) – are the three pillars that provide the foundation for promoting and protecting U.S. national security interests abroad.1 The 3D Planning Group (3DPG) was chartered to develop products and processes to improve collaboration in planning among these three organizations. This updated 3D Planning Guide (Guide), is a reference tool designed to help planners understand the purpose of each agency’s plans, the processes that generate them, and, most importantly, to help identify opportunities for coordination among the three. It is part of a larger effort to build understanding and synchronize plans to improve collaboration, coordination, and unity of effort.