Research has consistently demonstrated a link between certain personality disorders (PDs) and increased rates of aggression and violence. At present, understanding of the mechanisms that underlie this relationship is limited. This study was designed to examine the contention (Gilbert & Daffern, 2011) that the application of a contemporary psychological aggression theory, the General Aggression Model (GAM; Anderson & Bushman, 2002), may assist in elucidating the PD-aggression relationship. Eighty-seven offenders undergoing presentence evaluation were assessed for Axis II PDs and psychopathy, aggression, and three constructs delineated by the GAM: scripts, normative beliefs, and anger. Regression analyses were undertaken to examine the relative contributions of these variables to aggression. The results upheld a relationship between several PDs and aggression, and suggested that for these PDs, the consideration of scripts, beliefs supportive of aggression, and anger facilitated an improved understanding of aggressiveness. Overall, the findings indicate that the GAM offers valuable insight into the psychological features that characterize individuals with PD who are prone to aggression.