Two hundred and sixty men entering an inpatient program for alcohol and drug treatment were interviewed and tested for cognitive disturbances and hepatic function. When the treatment group was separated by the presence or absence of antisocial personality disorder, the antisocial group was distinguished by several factors. Antisocial alcoholics were more likely to have an early onset of alcoholism and to be involved with other illicit drugs, and showed evidence of more problems with control of their drinking. They reported more alcohol-related problems as defined in DSM-III. Despite histories of a more severe form of alcoholism, the antisocials were no more likely to develop alcohol dependence or show signs of cognitive or hepatic toxicity.