The aim of the Disarmament, Demobilization and Reintegration (DDR) process is to contribute to security and stability in post-conflict situations so that recovery and development can begin. The DDR of ex-combatants is a complex process, with political, military, security, humanitarian and socioeconomic dimensions. It aims to deal with the post-conflict security problem that results from ex-combatants being left without livelihoods or support networks---other than their former comrades---during the critical transition period from conflict to peace and development. This course will help UN and national decision makers, as well as UN, national and NGO practitioners, to understand the aims, objectives and practical issues related to a DDR process. It will present different policies and strategies for the development, management and evaluation of a DDR programme based on the International DDR Standards (IDDRS), which consolidate over 15 years of UN lessons and good practises on DDR issues.