The objective of this study was to introduce a new surgical treatment for drug-resistant chronic cluster headaches (CH). Because recent functional studies suggested that a hyperactivity of the posterior hypothalamus might be the primary cause of Cluster Headaches (CH) bouts, we designed a prospective study to explore the therapeutic effectiveness of chronic high-frequency stimulation of this region for the treatment of CH. Nine electrodes were stereotactically implanted in the posterior hypothalamus in eight patients suffering from intractable chronic CH. The stereotactic coordinates of the targeted area were 3 mm behind the mid-commissural point, 5 mm below the mid-commissural point, and 2 mm lateral from the midline. Since initiating this treatment in our center, all of the eight patients have improved. Steroid administration has been progressively withdrawn. All of the patients reported that they were pain-free at 1-26 months of follow-up. Three of the eight patients were pain-free without any medication while five of the eight required low doses of methysergide and/or verapamil. No noxious side effects from chronic high-frequency hypothalamic stimulation have been observed nor have we encountered any acute complications from the implant procedure. Tolerance was not observed. We conclude that these preliminary results indicate that hypothalamic stimulation is safe and effective for the treatment of drug-resistant, chronic CH. In addition, these data confirm the "central" pathogenesis for chronic CH.