This chapter reviews the identification, testing, and 8- to 12-year follow-up of 237 sons of alcoholic fathers and 237 controls (474 men). Subjects were selected from respondents to a questionnaire mailed to 18- to 25-year-old students and nonacademic staff at a university, with initial evaluations demonstrating few differences between sons of alcoholics and controls on quantity and frequency of drinking or many major life problems related to alcohol. The subset of 474 men actually tested in the laboratory also revealed few family history differences on personality attributes, including a lack of differential on the Type 1/Type 2 alcoholism scheme. Our laboratory has, however, consistently documented less intense responses to alcohol for the sons of alcoholics, findings consistent across subjective feelings, increases in body sway, and changes in several hormones and electrophysiological measures. This dampened response to ethanol for men at high future risk for alcoholism was not observed after challenges with two different doses of diazepam.