While there is no research evidence to contradict the notion that individuals with a recent or distant history of violence are likely to repeat the violence, prediction is complicated by the complex interaction of individual predispositional and situational factors. In general, many findings suggest the limited reliability and validity of predictions of dangerousness, as well as a high rate of false positives. In two decisions, the U.S. Supreme Court upheld the constitutionality of using predictions of dangerousness in sentencing and pretrial detention decisions, although it also noted problems with the accuracy of such predictions. Despite these problems, a number of indicators are available to clinicians that suggest a behavioral tendency, proclivity, or even probability of future violence and that can provide justification for taking preventive action. A classification system based on an endogenous-exogenous motivational spectrum, coupled with an analysis of offense/offender factors (environmental, situational, catathymic, impulsive, and compulsive), can aid in prognosis and disposition. 1 table and approximately 175 references.