Fetal Alcohol Spectrum Disorders (FASDs) represent a continuum of development disabilities associated with maternal consumption of alcohol during pregnancy. This spectrum of disorders, which includes the Fetal Alcohol Syndrome (FAS), is characterized by a wide range of physical, cognitive, and behavioral impairments. Estimates of the number of live births in the United States meeting criteria for a diagnosis of FAS range from .5 to 2 infants per 1,000, with the prevalence of the entire continuum of FASDs estimated to be I in 100. This paper discusses some of the complexities involved in diagnosing individuals affected by prenatal alcohol exposure, provides a review of the neurocognitive and neurobehavioral deficits commonly seen in this population, and examines how such deficits may manifest during different developmental periods across the life span. Additionally, strategies for assessing these deficits are described, and specific measures that are appropriate for alcohol-exposed individuals are presented. The challenges of working with this under-identified and underserved population are highlighted, as well as the importance of early diagnosis and intervention.