Electroencephalographic, autonomic and subjective reactions to alcohol were examined among 78 young nonalcoholic men, cross-classified with respect to the presence/absence of a family history of alcoholism (FH) and the presence/absence of a personal history of antisocial personality disorder (ASP). Both an alcohol placebo and alcohol (0.32 ml/kg) were administered in a single laboratory session. The four groups of subjects were compared at baseline, and at several discrete time points before and after consumption of placebo and alcoholic beverages. During the baseline period, ASP+ subjects exhibited significantly more body sway and faster frontal EEG activity than their ASP- counterparts. The combination of ASP with FH was associated, at baseline, with an excessive amount of high frequency (18.6-27.6 Hz) beta activity in the right frontal EEG. After beverage consumption, several significant FH effects emerged that were independent of the effects of ASP. After placebo consumption, FH+ subjects exhibited significantly more fast alpha (10.9-12.5 Hz) activity at the right frontal electrode than FH- subjects. This difference persisted until blood alcohol concentrations began to rise, at which time fast alpha activity in FH+ subjects declined to FH- levels. Differences between the two FH groups were also apparent in their subjective reactions to the placebo and alcoholic beverages. Relative to FH- subjects, FH+ subjects rated themselves as more intoxicated after consuming the placebo but less intoxicated after consuming alcohol. FH+ subjects expressed greater confidence in their ability to resist the offer of an alcoholic drink across most time points.