It is noted that rapists vary in their psychodynamic characteristics, but all use psychological or physical violence on their victims. Minor sex offenders do not necessarily escalate to major offenses, however. In terms of treatment, the penile plethysmograph is a significant advance in the identification of men who become sexually stimulated mainly by violent stimuli. The best treatment for sexually violent offenders is a combination of psychotherapy, behavioral therapy, and hormonal treatment. Blood levels of hormone and the individual's behavior both need monitoring following treatment. Further research should focus on how women may deter potential attackers and on how to identify early risk factors associated with sexual violence. 15 references.