Objective: To examine unique and relative predictive values of demographic, social learning, developmental, psychopathology, and dyadic variables as risk factors for perpetration of intimate partner physical aggression in a national sample of married or cohabiting individuals. Method: Men (n = 798) and women (n = 770) were selected from the public use data file of the 2003 National Comorbidity Survey Replication (NCS-R) which used a multistage cluster sampling design. Results: Eight percent of women and 5% of men reported perpetrating physical aggression in the past year. Based on multivariable regression analyses, among men, the unique risk factors for perpetrating physical aggression were parental violence, dating before age 14, dating aggression, Intermittent Explosive Disorder (IED) before and after age 20, and being victimized by partner. Among women, significant risk factors were younger age, dating aggression, IED before age 20, cohabiting, victimization by partner, and marital/relationship strain. Conclusions: A number of social learning, developmental, adult psychopathology, and dyadic factors were significant. Two dyadic variables, victimization and marital strain, had by far the strongest associations with perpetration of partner aggression. Given that dating aggression and early IED were risk factors for male and female IPV much later in life suggests early interventions for those at risk. (PsycINFO Database Record (c) 2014 APA, all rights reserved)