Nonalcoholic men with high-density family histories of alcohol dependence (high risk) were compared with men with negative family histories (low risk) on a differential classical conditioning protocol that examined the acquisition of conditioned skin conductance responses (SCRs) to a tone (CS+) signaling the occurrence of an electric shock. High-risk Ss had significantly smaller SCRs to the CS+ tone probes during the acquisition phase and poor response discrimination between CS+ probes and CS- tones that were not paired with shock. The low-risk Ss showed a consistent pattern of discrimination between the CS+ and CS- tones. Unresponsivity to the CS+ probes was significantly related to more alcohol-related problems. The results suggest a relationship between risk for alcohol abuse and poor conditioning to signals for punishment, possibly reflecting weak behavioral inhibition system processes (D. C. Fowles, 1987).