The offspring of 28 women who reported light to moderate cocaine use during pregnancy were compared with those of 523 women who reported no cocaine use during pregnancy and none for the year prior to pregnancy. Subjects were participants in two prospective, longitudinal studies of prenatal substance use. Women were interviewed during their fourth and seventh months of pregnancy, at delivery, and at 8, 18, 36, and 72 months postpartum regarding cocaine, alcohol, marijuana, tobacco, and other drug use. At 6 years, children underwent physical examination, and their cognitive development, academic achievement, and behavior were assessed. The women in the cocaine group were more likely to be Caucasian and to use more alcohol, marijuana, tobacco, and other illicit drugs than those in the comparison group. When demographic and substance use differences between the groups were controlled, there were no significant effects of prenatal cocaine exposure on the growth, intellectual ability, academic achievement, or teacher-rated classroom behavior of the 6-year-old offspring. Children prenatally exposed to cocaine did show deficits in their ability to sustain attention on a computerized vigilance task.