Results of the study identified distinct subgroups of primary and secondary psychopaths as were identified in prior studies. In general the results show that psychopathy subtypes are replicable across methods. Furthermore, comparisons on other variables provide external validation of the subtypes consistent with prior theoretical conceptualizations. The cluster analysis identified a group of individuals that appeared to be consistent with the prior conceptualization of the psychopath and prior conceptualization of the primary psychopath. Primary psychopaths were found to have lower anxiety scores than secondary psychopaths. Prior studies were also replicated in that members of this group were charged with a greater number of violent crimes. Consistent with prior findings, a second cluster of participants (secondary psychopaths) was characterized by higher anxiety or negative affectivity scores than all other clusters, along with considerable drug and alcohol problems. The finding that secondary psychopaths displayed criminal versatility similar to that of primary psychopaths is also consistent with prior findings. In addition to subgroups with psychopathic features, a cluster characterized by low scores on most measures (low-psychopathology criminals) was found. The analysis also found a fourth cluster (criminals with negative affect) that was clearly nonpsychopathic. Criminal offenders differ in important ways, and the classification of offenders into homogeneous groups has long been questioned. Tables, references