Older persons in the United States are at higher risk for suicide than any other segment of the population. The epidemiology and risk factors for suicide in later life and the most promising approaches to its prevention are reviewed. Available data suggest that psychiatric and physical illnesses, functional impairment, personality traits of neuroticism and low openness to experience, and social isolation are important correlates of late-life suicide. Affective illness is the risk factor with the strongest association. As treatable conditions in most cases, mood disorders are critical targets for preventive interventions. Because 70% of older adults who committed suicide saw their primary care provider within 30 days of death, the primary care setting is an important venue for intervention. Mood disorders are common in primary care practice, but often go undiagnosed and inadequately treated. One important approach to late-life suicide prevention, therefore, is to optimize the ability of primary care providers to diagnose and treat late-life mood disorders and suicidality effectively. Other elders at high risk have no active relationship to primary care. Strategies designed to identify this group and provide them with preventive services through outreach to the community have shown promise as late-life suicide prevention measures as well.