In this essay, Winnicott states that the basis for a study of actual aggression must be a study of the roots of aggressive intention. The main source of aggression is instinctual experience. In the stage of what Winnicott calls Pre-Concern, aggression is a part of love. If it is lost at this stage of emotional development there is some degree of loss of the capacity to love; to make relationships with objects. During the Stage of Concern there are innocent aggressive impulses towards frustrating objects, and guilt-productive aggressive impulses towards good objects. With the phase he describes as the Growth of Inner World, the child becomes concerned with the effect on his mother of his impulses, and the results of his experiences in his own self. A complex series of defence mechanisms develops, which should be examined in any attempt to understand aggression in a child who has reached this stage. A state of what looks like delusional madness easily appears through the child’s projection of inner world experience out onto his objects. All being well through these stages, aggression then can come to have social value.