How do societies emerging from war come to terms with their recent violent past? How can people and communities, which are deeply divided and traumatized by war and gross human rights violations, regain trust in their fellow citizens and state institutions? How can they achieve a sense of security and economic stability, rebuild a system of shared values, participatory political structures and an inclusive identity? How can a past that is marked by violence be overcome, and a common future shaped? The peaceful transformation of post-conflict societies is undoubtedly a long and complex process, which ultimately has to involve all layers and structures of a society. However, experience gained over past decades has shown that restoring justice and the rule of law, truth-seeking mechanisms and the development of new social relationships are central to this process. This FriEnt Briefing Paper explains terminology and concepts of relevance to transitional justice, identifies key challenges and issues arising for development and peace organisations, highlights the most significant problems, and outlines strategies for action.