Throughout the last decades the Psychology of criminal conduct, that agglutinates scientific knowledge around the criminal phenomena, has emerged. Among their scientific main interests they are the following: the explanation of antisocial behavior (where the learning theories are outstanding), the analyses of the individual characteristics, the hypotheses strain-aggression, the studies on social links and crime, and the analyses of criminal careers. This last topic, also denominated 'developmental criminology, investigates the relationship that the beginning and maintenance of the criminal activity keep with diverse risk predictors (singular and social, static and dynamic). Their results have had great relevance for the design of crime prevention and treatment programs. The psychological treatments of offenders are guided to modify those factors of risk, well-known as 'criminogenic needs', that are considered directly related with their criminal activity. In short the treatment programs try to train the criminals (youth, partner violence offenders, sexual aggressors, etc.) in new repertoires of social behavior, try to develop their thought, to regulate their choleric emotions, and to prevent the relapses or recidivisms in crime. Lastly, the Psychology of the criminal conduct puts a special emphasis at the present time in the prediction and management of the risk of violent and antisocial behaviors, field to which will be devoted a later paper of this same monograph.