Tracing the history of the category of antisocial personality disorder, this study reveals its emergence is linked to particular kinds of governing, rather than simply to advances in the human sciences or a means of social control. David McCallum examines key legal and institutional developments in Australia, the U.K, and the U.S. as well as parallel developments within psychiatry and psychological medicine. Applying a social theoretical analysis to this material, he challenges our assumptions about the formation and control concepts of dangerousness and personality.