The relationship between mental disorder, violent crime, and psychopathic disorder is only touched upon, since this has been the subject of detailed consideration by others. In a discussion of "context," the author notes that since much criminal behavior is arbitrarily defined and there are arguments about the existence and definition of mental disorder, there are difficulties in trying to establish connections between these two ill-defined and complex forms of behavior. Despite these difficulties, it is still important to try to examine some of their possible relationships, while acknowledging that any conclusions must be tentative. The next section of the paper reviews studies of penal and criminal populations that are relevant to the purpose of this overview. It concludes that after having made allowance for methodological shortcomings, the overall impression from most of the studies reviewed is that severe psychiatric illness (psychosis), organic disorders, and serious mental handicap are uncommon in criminal populations, but personality disorders (which may be accompanied by various forms of formal mental illness or mental impairment) and alcohol and other drug-related problems are prevalent in criminal populations. A review of research on criminality in psychiatric populations yields few definitive conclusions due to the sparseness of such research. Another section of the paper explores the relationship between some specific mental disorders and criminal behavior. The concluding section discusses the legal implications for the criminal processing of mentally ill persons and the subsequent management of such persons. 90 references