A sample of 81 male prisoners that demonstrated the most extreme forms of behavioral disorder within the penal setting was studied for the purpose of examining links between their underlying psychopathology and patterns of dangerous and disruptive behavior, mediated through a series of potentially motivating variables. Research diagnostic instruments were used, as well as an item sheet measuring disruptive behaviors and their motivations. Independent associations were established using logistic regression. The results show specific associations between psychopathy and axis II disorders with violent and disruptive behavior and motivations for these behaviors. Antisocial personality disorder was highly prevalent and therefore did not discriminate well between different motivational variables. Narcissistic subjects were likely to have exhibited violence against both inmates and staff, and to have been involved in incidents of cell barricading. The study demonstrates that assessment of axis II personality disorder is of major importance in the assessment of dangerous and disruptive prisoners. Personality disorders act as predisposing factors influencing the development of motivations and facilitate the enactment of disordered behavior, in a linear progression. Assessment of personality disorder should be routine in disruptive and dangerous prisoners. Future developments should include a more complex, longitudinal approach. The major challenge is to resolve the difficulties in predicting which situational factors are most important in precipitating examples of behavioral disorder in the presence of an axis II personality disorder. 1 figure, 7 tables, 39 references