Fetal alcohol syndrome (FAS) is a common cause of developmental disability, neuropsychiatric impairment and birth defects. The disorder is identified by the presence of growth impairment, central nervous system dysfunction, and a characteristic pattern of craniofacial features. The reported prevalence of the disorder varies widely and recent estimates approach 1% of live births. Expression of these features varies by age. People with FAS have high rates of comorbid conditions: attention deficit hyperactivity disorder (40%), mental retardation (15-20%), learning disorders (25%), speech and language disorders (30%), sensory impairment (30%), cerebral palsy (4%), epilepsy (8-10%). Birth defects are common. In the United States, the annual birth cohort of persons with FAS could be as high as 39,000 cases annually. Cause-specific mortality is 6% for patients with FAS. The disorder is expensive to treat and most patients have lifelong impairment. The annual cost of care in the United States would approach US$5.0 billion. Early recognition and entry into appropriate treatment programs appear to improve outcome. Prevention efforts should involve screening for alcohol use prior to pregnancy and at the first prenatal care visit.