This article summarizes research findings on psychosocial risk factors for late life depressive disorders. The article draws heavily on longitudinal cohort studies of well-defined, population-based samples with diagnostic measures that assess the risk of incident or new-onset depressive episodes. These studies have identified a number of significant psychosocial risk factors for late life depressive disorders, including life events and ongoing difficulties; death of a spouse or other loved one; medical illness and injuries; disability and functional decline; and lack of social contact. Additional evidence suggests that the impact of these psychosocial risk factors on depression can be enhanced or buffered by personal or environmental factors. Although many of these psychosocial risk factors are more prevalent among older than younger adults, it is not clear that their impact on the risk of depression differs by age. Methodological challenges to advancing research on psychosocial risk factors for late life depression are reviewed, including problems related to study designs, sample selection, and measurement.