Although individuals with intellectual and developmental disabilities (ID/DD) consume alcohol at lower rates than do individuals without these disabilities, those who do consume alcohol are highly vulnerable to abusing it. As a result, individuals with ID/DD are a growing health disparities population and, compared to individuals without these disabilities, are at increased risk of physical disease; psychological injury; social, behavioral, financial, vocational, and legal consequences; further disability; and even death. This entry reviews the prominent theory of alcohol abuse, heightened risk factors, impact, treatment concerns, and future directions for this population.