Collective violence is a critical concern worldwide. This article explores how the recent changes in the nature of conflicts – having evolved from the classic “Clausewitzian” to what is called “identity conflicts” – bring to the fore psychosocial community and individual issues that had never been seen before the Cold War. We shall see how humanitarian assistance in complex emergencies brings us a wealth of information and experience in the field of collective psychological trauma and victimization. A strict notion of “mental health” which is derived from a strictly Western based medical model, has evolved into a “psychosocial” view that empowers whole communities to explore their traditional resources and values as well as their resilience in the face of protracted conflict.