The population of elderly in the United States with substance use disorders (SUDs) is growing appreciably. SUDs among the elderly are often associated with poor outcomes and are frequently underdiagnosed. The current diagnostic criteria are less sensitive in identifying SUDs among the elderly. Routine screening with validated screening tools may improve the diagnosis of SUDs among the elderly. There is a dearth of data from controlled studies on SUDs among the elderly and the use of pharmacologic agents for treatment, although data indicate that older adults with SUDs respond well to treatments that are specifically designed for this age group.