1. Subjects with frequent tension headaches 2. Subjects with ill-defined head pain 3. Unable to be weaned off other headache prophylaxis. 4. Requiring daily use of centrally-acting medications. 5. Pregnant, lactating and women not on adequate birth control measures. 6. Subjects with a personal or family history of seizures of any type. 7. History of head injury or brain surgery. 8. Cardiac pacemakers or any other implanted electronic device. 9. Subjects with history of headaches or with history of tension-type headaches recurring >1/month and relieved by over the counter medications.