Major depressive disorder is a potentially debilitating condition that often is unrecognized or undertreated in the elderly. Even when aggressively treated, the course of geriatric depression can be severe. There is growing evidence that suggests that late-life depression may carry a higher illness burden than depression with onset earlier in life, and that severity is linked to medical and psychiatric comorbidity. Data continue to accumulate in support of various treatment modalities, including medication, electroconvulsive therapy, and psychotherapy. Given the increased risk of adverse outcomes associated with geriatric depression, such as dementia and suicide, it is essential that future investigations continue to build on the evidence base supporting improved diagnosis and treatment of this complex disorder.