SummaryAdvanced age is associated with an increased prevalence of depressive symptoms, but not of primary major depression. The increasing prevalence of disability and institutionalization with age contributes to the increase in depressive symptoms, but age-associated declines in dopaminergic and noradrenergic reserves may also play a role. In late-life depression, vegetative symptoms may predominate over mood changes, and symptoms may be misattributed to systemic illness; these problems may confound the diagnostic process. The outcome of late-life depression is influenced by comorbid personality disorders; although these occur frequently, they are poorly studied. Treatment of late-life depression may ameliorate physical disability. A naturalistic study of nursing home patients suggests that antidepressants may help disability even when depressive symptoms do not reach the threshold for formal psychiatric diagnosis.