The basic puzzle underlying this seminar is the question of how societies torn apart by years, often decades, of violent conflict and mass atrocities can be stabilized, and how they can be reconciled. Negative peace signifies merely the absence of overt conflict, while hostile attitudes and structural grievances that gave rise to the conflict in the first place may still exist. Positive peace, by contrast, requires more than justthe absence of hostile behavior – it implies that the conflict parties’ attitudes towards one another are transformed, and that structural inequalities and grievances are addressed in an appropriate fashion. Whereas peacekeeping seeks to achieve negative peace, conflict transformation and peacebuilding arefar more ambitious projects in that they aim at establishing positive peace. In this seminar, we will look at different approaches to building lasting peace in conflict-riddensocieties. Drawing on an interdisciplinary literature from the fields of Political Science, (Social) Psychology, and International Law, we will explore the explanatory factors that account for the successes and failures of these approaches, and discuss how macro- and micro level variables interact in transforming conflict into peace.