A group of eight patients with severe depression lasting 6 years or longer were treated with anterior capsulotomy and followed prospectively. Stereotactic surgery was used to produce radiofrequency lesions in the anterior limbs of both internal capsules. For all patients, there are follow-up data for at least 24 months. At 24-to-36 months postoperatively, four patients were either not-depressed or mildly depressed; one was mildly-to-moderately depressed; one was moderately-to-severely depressed; and only one remained severely depressed. One patient developed a progressive vascular dementia with parkinsonism caused by autopsy-proven arteriolosclerosis.