Motor coordination was assessed in two samples of adult subjects: one sample (n = 90) included adults previously diagnosed with one of a number of Fetal Alcohol Spectrum Disorders (FASD) and comparison peers, the second was a prospective longitudinal study of adults who were exposed to varying levels of alcohol as fetuses (n = 402). This comparative analysis sought to determine whether motor effects seen in both clinical and nonclinical children persist into adulthood, whether any individual motor tasks show significant effects of prenatal alcohol exposure across the age range, and whether motor assessments of adults have any role in diagnostic strategies for adults suspected of FASD. Motor tests included balance and unilateral, bilateral, finger, hand and foot coordination. Three-quarters of the subjects with FASD demonstrated deficits in motor function outside the range of comparison subjects. Adults with FASD performed more poorly, on average, on all individual tests including balance and fine motor control. In the prospective longitudinal sample, only subjects who had been previously identified in childhood as having a possible diagnosis on the Fetal Alcohol Spectrum were still in deficit as adults on motor tasks, relative to comparison subjects. Thus, the dose-dependent motor coordination effects of alcohol previously found in children do not appear to persist into adulthood, except in those most highly exposed children who also have other accompanying neuropsychological effects in childhood.