Since 1914 Psychology has generally been practised in contexts dominated by war, either as a current, recent or prospective reality, and continues to do so. Unsurprisingly then this has left a deep imprint on the discipline. War presents Psychology with a dilemma. The majority of, if not quite all, modern psychologists accept that war is an evil pathology (particularly in its current forms). This being so, their task should, presumably, be to diagnose its psychological roots. Such principled opposition to war is nevertheless offset by the fact that most (if again not quite all) psychologists, no less than anyone else, usually feel bound to support the war efforts of their host societies. Psychologists have been called upon increasingly to deploy their professional skills in such tasks as selection and training, propaganda, designing military technology and most recently the interrogation of prisoners. Perennially statusconscious, they have often welcomed the opportunities war offers for forging links with other, ‘harder’, disciplines. Wartime provides abundant scientific funding and research opportunities, and Psychology, like other disciplines, has had few inhibitions in exploiting these. This does not imply cynicism; in the final analysis the psychologist’s own fundamental identification is generally with national war aims. If the roots of the conflict appear to lie in the psychological character of the enemy, then the implicit dilemma between cure and combat is easily evaded. Since the First World War psychologists have also become clinically involved in the treatment of those suffering war-related mental disturbances of various kinds, primarily though not exclusively military personnel traumatised by combat, victims of ‘shell-shock’ or ‘combat fatigue’ (categories which were of course created by psychologists undertaking this work, although an ancestral condition, ‘cannon-ball wind’, was known from the early nineteenth century).