Antisocial Personality Disorder (APD) and PCL-R psychopathy are critically examined regarding their application to sentencing determinations. PCL-R psychopathy is emerging in the literature as a more useful forensic diagnostic construct than APD, which appears flawed by multiple weaknesses. These include shifting diagnostic criteria, innumeracy problems, absence of symptom weighting, temporal instability, and the equivalence of some symptoms with substance abuse disorders. Additionally, APD overdiagnosis may result from inattention to issues of social context, trauma history, and symptom pervasiveness. Neither objective nor projective personality testing reliably differentiates APD. Finally, an APD diagnosis does not always indicate criminal, much less incorrigible criminal behavior. By contrast, PCL-R psychopathy results are strongly predictive of criminal behavior and violent recidivism for Caucasian males through mid-life residing in the community. Emerging research with the PCL-R regarding other important populations and contexts is promising but generalization is currently limited.