The goal of this project is to help improve the value and character of defense resource planning in an era of growing uncertainty and complex strategic challenges. Because it is impossible to predict what threats may arise and how defense funding will progress, a new approach is needed to develop robust resource strategies, that is, strategies that perform well over a wide range of threat and funding futures and thus are better at managing surprise. To address this need, RAND researchers applied a proven approach to strategy discovery, Robust Decision Making, or RDM, to defense planning. RDM, a quantitative decision support methodology for informing decisions under conditions of deep uncertainty and complexity, has been applied to many policy areas in the last decade. This document explores how the RDM method may be applied to defense resource planning in an application to air-delivered conventional munitions mix planning. This research was conducted under the sponsorship of the Cost Assessment and Program Evaluation (CAPE) Directorate within the Office of the Secretary of Defense (OSD) by the International Security and Defense Policy Center of the RAND National Defense Research Institute, a federally funded research and development center sponsored by the Office of the Secretary of Defense, the Joint Staff, the Unified Combatant Commands, the Navy, the Marine Corps, the defense agencies, and the defense Intelligence Community.