It is a pleasure to introduce edition number fi ve of The Psychology of Criminal Conduct (PCC-5). As in PCC-1 through PCC-4, we update research, theory, and applications in PCC-5. PCC-5 remains true to its original intent of developing a holistic and truly interdisciplinary general personality and social psychology of criminal conduct. We draw upon a variety of theoretical positions on variability in the criminal behavior of individual human beings but once again fi nd particular value in general personality and cognitive-behavioral and cognitive social learning perspectives on human behavior in general and criminal behavior in particular. We remain open to the full range of potential variables of interest from the biological through the personal, interpersonal, familial, structural/ cultural, political/economic, and the immediate situations of action. An outstanding change in criminology, forensic mental health, and criminal justice over the last 20 years has been the enhanced position of PCC academically and in practice. Indeed, applications of PCC have revolutionized corrections and forensic mental health in many areas of North America, Europe, Australia, and New Zealand. In applied terms, prevention and corrections have moved from “nothing works” through “what works” to “making what works work.” All of this occurred in a political/judicial environment that was preoccupied with “getting tough.”