A five-year retrospective study was conducted with patients who had completed training with thermal and electromyograph feedback and muscle relaxation exercises. The purpose was to examine the long-term effects of biofeedback training on headache problems. A questionnaire was mailed to all 556 patients who had completed training between September, 1972 and January, 1977. Patients were asked to measure the effects of biofeedback training on their headache problems, i.e., no improvement, transient improvement, or long-term improvement. 407 questionnaires were completed and returned. The role of such variables as age at time of training, sex, the presence of a habituation problem prior to training, and time elapsed since training were analysed and found to significantly influence the success of biofeedback training. A trend was seen within the diagnosis variable. The most successful biofeedback candidate was found to be a female under 30 years of age who was not habituated to medication and without depressive symptoms, diagnosed as suffering from vascular headaches. It can be concluded from the results that biofeedback training is a successful form of therapy in treating headache problems.