Objective: Despite the growth of geriatric home health services, little is known about the mental health needs of geriatric patients seen in their homes. The authors report the distribution, correlates, and treatment status of DSM-IV major depression in a random sample of elderly patients receiving home health care for medical or surgical problems. Method: Geriatric patients newly admitted to a large, traditional visiting nurse agency were sampled on a weekly basis over a period of 2 years. The 539 patients ranged in age from 65 to 102 years; 351 (65%) were women, and 81 (15%) were nonwhite. The Structured Clinical Interview for DSM-IV Axis I Disorders was used to interview patients and informants. The authors reviewed the results of these interviews plus the patients' medical charts to generate a best-estimate DSM-IV psychiatric diagnosis. Results: The patients had substantial medical burden and disability. According to DSM-IV criteria, 73 (13.5%) of the 539 patients were diagnosed with major depression. Most of these patients (N=52, 71%) were experiencing their first episode of depression, and the episode had lasted for more than 2 months in most patients (N=57, 78%). Major depression was significantly associated with medical morbidity, instrumental activities of daily living disability, reported pain, and a past history of depression but not with cognitive function or sociodemographic factors. Only 16 (22%) of the depressed patients were receiving antidepressant treatment, and none was receiving psychotherapy. Five (31%) of the 16 patients receiving antidepressants were prescribed subtherapeutic doses, and two (18%) of the 11 who were prescribed appropriate doses reported not complying with their antidepressant treatment. Conclusions: Geriatric major depression is twice as common in patients receiving home care as in those receiving primary care. Most depressions in patients receiving home care are untreated. The poor medical and functional status of these patients and the complex organizational structure of home health care pose a challenge for determining safe and effective strategies for treating depressed elderly home care patients.