Although psychopathy usually is treated as a unitary construct, a seminal theory posits that there are 2 variants: Primary psychopathy is underpinned by an inherited affective deficit, whereas secondary psychopathy reflects an acquired affective disturbance. The authors investigated whether psychopathy phenotypically may be disaggregated into such types in a sample of 367 prison inmates convicted of violent crimes. Model-based cluster analysis of the Revised Psychopathy Checklist (PCL-R; R. D. Hare, 2003) and trait anxiety scores in the psychopathic subgroup (n = 123; PCL-R > or = 29) revealed 2 clusters. Relative to primary psychopaths, secondary psychopaths had greater trait anxiety, fewer psychopathic traits, and comparable levels of antisocial behavior. Across validation variables, secondary psychopaths manifested more borderline personality features, poorer interpersonal functioning (e.g., irritability, withdrawal, poor assertiveness), and more symptoms of major mental disorder than primary psychopaths. When compared with the nonpsychopathic subgroup (n = 243), the 2 psychopathic variants manifested a theoretically coherent pattern of differences. Implications for etiological research and violence prevention are discussed.