We evaluated the relationship of antisociality to 7-month treatment response in 224 alcohol-and/or cocaine-dependent men. Subjects with and without a DSM-III antisocial personality disorder (ASPD) responded similarly and positively to treatment in a number of functional domains, including substance use. A more detailed analysis comparing subjects with ASPD, subjects meeting adult but not childhood ASPD criteria (A-ASPD), and subjects meeting neither adult nor childhood ASPD criteria (pure non-ASPD) revealed similar and positive responses to treatment among the three groups. The antisocial groups had more cocaine and alcohol use at the baseline evaluation, but at 7-month follow-up, they had levels of use not significantly different than the pure non-ASPD group. The findings suggest that an ASPD diagnosis or an adult antisocial lifestyle, at least as measured by DSM-III criteria, does not predict short-term treatment response.