Although biofeedback was developed by psychologists, it has been most widely used in the treatment of psychophysiological and medical disorders and less frequently used to control symptoms of psychopathology and mental disorders. The authors review studies in which biofeedback was used in the treatment of patients with schizophrenia, depression, anxiety disorders, insomnia, alcobol and drug dependence, and tardive dyskinesia. The studies indicate that biofeedback can help selected patients modify specific responses or response patterns associated with a mental disorder. It appears to be most suitable for patients and disorders in which physiological processes can be identified as relevant. However, the findings offer little support for biofeedback as the treatment of choice for any mental disorder.