For decades, it has been known that the Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnosis of Antisocial Personality Disorder (ASPD) is a nonadequate operationalization of psychopathy (Crego & Widiger, 2015). The DSM-5 alternative model of personality disorders provides an opportunity to rectify some of these long held concerns. The current study compared the Section III alternative model's trait-based conception of ASPD with the categorical model from the main diagnostic codes section of DSM-5 in terms of associations with differing models of psychopathy. We also evaluated the validity of the trait-based conception more broadly in relation to measures of antisocial tendencies as well as psychopathy. Participants were 200 male inmates who were administered a battery of self-report and interview-based researcher rating measures of relevant constructs. Analyses showed that Section III ASPD outperformed Section II ASPD in predicting scores on Hare's (2003) Psychopathy Checklist-Revised (PCL-R; r = .88 vs. .59). Additionally, aggregate scores for Section III ASPD performed well in capturing variance in differing ASPD and psychopathy measures. Finally, we found that the Section III ASPD impairment criteria added incrementally to the Section III ASPD traits in predicting PCL-R psychopathy and SCID-II ASPD.