This book explores the obstacles to peacebuilding, and how they have evolved, in a rigorous, referenced way, through the use of case studies and statistical evidence. The authors focus in particular on the much neglected economic area, whereby building more effective states and replacing the war economy has acquired a new sense of urgency since extremist groups increasingly recruit people by providing services and jobs to those deprived of them due to government and economic failures. The authors build a strong case for supporting the institutional and technical recommendations on how to move forward, based on past lessons, best practices in war-torn countries, and relevant case studies.