Fetal alcohol spectrum disorders constitute a major public health problem. This article presents an overview of important issues that surround these disorders and emphasizes the structural and neurobehavioral consequences associated with prenatal exposure to alcohol. Diagnostic criteria are discussed, and possible moderating factors for the range of outcomes are mentioned. In addition, the prevalence of fetal alcohol spectrum disorders is described, and estimates of the financial impact of these disorders are given. Heavy prenatal alcohol exposure can severely affect the physical and neurobehavioral development of a child. Autopsy and brain imaging studies indicate reductions and abnormalities in overall brain size and shape, specifically in structures such as the cerebellum, basal ganglia, and corpus callosum. A wide range of neuropsychological deficits have been found in children prenatally exposed to alcohol, including deficits in visuospatial functioning, verbal and nonverbal learning, attention, and executive functioning. These children also exhibit a variety of behavioral problems that can further affect their daily functioning. Children exposed to alcohol prenatally, with and without the physical features of fetal alcohol syndrome, display qualitatively similar deficits. Determining the behavioral phenotypes that result from heavy prenatal alcohol exposure is critical, because the identification of these children is crucial for early interventions. In addition, knowing which brain areas are involved might enable the development of better intervention strategies. However, intervention needs to go beyond the affected individual to prevent future cases. As evidenced by the staggering financial impact these disorders have on society, prevention efforts need to be aimed at high-risk groups, and this issue needs to be made a high priority in terms of public health.