Event-related potentials (ERPs), particularly the P3 wave, have been proposed as biological markers of genetic risk for alcoholism. The present study assesses the ERPs from 102 boys and girls (7 to 15 years old) divided into three groups: two groups of sons and daughters of alcoholic fathers, with and without other first- or second-degree relatives affected, and a control group of children of nonal-coholics. Both visual and auditory discrimination tasks with three stimuli (standard, target, and infrequent nontarget) were used. P3 amplitudes did not reach significant reduction for the high-risk males and were complex for females. There were significant differences among females in P3 visual latency elicited by targets; delays in this variable were associated with multigenerational familial alcoholism. Results are discussed in light of the tasks used for eliciting the ERPs and the characteristics of the selected sample.