This chapter draws together historical, social and psychotherapeutic strands as they contribute to the background of debriefing and its evolution. Its relation to military psychiatry, crisis intervention, narrative tradition, psychoeducation, grief counselling, group psychotherapy, behavioural and cognitive therapies, and psychopharmacology are touched upon and their implications for an eclectic model is considered. Acute preventive interventions can be implemented only if there is a broad acceptance of a notion of collective responsibility and the value of group survival of caring for such individuals. The essence of crisis intervention is that a clear precipitant exists and that the individual's distress is clear. If individuals with a normal biological stress response do not develop post-traumatic stress disorder (PTSD), it raises questions of whether early and immediate interventions may modify the nature of the acute stress response in such a way as to increase the risk of PTSD.