Although psychological characteristics of both cocaine addicts and alcoholics are well-documented, less information is available focusing on those patients who are dependent on both drugs. This study was designed to assess the differences between cocaine- and cocaine-plus-alcohol-dependent inpatients along several psychological variables. Of the 144 men that served as subjects, 113 were cocaine dependent (CD) and 31 were dependent on both cocaine and alcohol (CD–AD). CD–AD subjects showed significantly more symptoms of depression and anxiety and were more likely to have antisocial and avoidant personality disorders. The CD–AD group scored higher overall on the Minnesota Multiphasic Personality Inventory clinical scales. These results suggest that patients dependent on both cocaine and alcohol require increased attention to psychopathology during treatment.