The author explores our psychological need for enemies and the contribution this makes to overt conflicts in the external world. Enemies serve as an opposite from which we can differentiate ourselves, either as an individual or as a group; they help us to define our physical and psychological boundaries. Enemies provide a target and an outlet for our aggression and also for the projection of the shadow. They also provide the stimulus to individuation, through the heroic encounter with the enemy in the unfamiliar world outside the home, particularly in adolescence. The psychic integration of ‘self’ and ‘enemy’ is explored as the outcome of individuation.