Attempting to pacify the emergent wars in the 1990s, the European Union mediation could not stop the vast destruction and prevent genocide from taking place right next door to the EU, the world's biggest peace project. In the 21st century, the Western Balkans region has again become a subject of testing the EU's "new" foreign policy instrument - mediation. This time, the EU assumed the role of a post-conflict mediator aiming to sustainably resolve the (intractable) conflicts in the post-war setting of the region. While its first mediations in the former Yugoslavia were unsuccessful, the EU's recent mediation attempts in the post-violent stage of the Balkans' conflicts have resulted in varied outcomes. Introducing a new model, this book explains the varying effectiveness of EU mediation in post-conflict and analyses the determining conditions of the EU mediation efficiency in post-conflict settings. The book is among the few publications that shed light on EU mediation utilized as an instrument of conflict resolution that aims to solve protracted conflicts in post-conflict settings.