Patients were selected for participation in the program if (1) theycomplained of severe sleep-maintenance insomnia and impairment of daytime function for 1 year or more, (2) a physical examination revealed no evidence of physical disorders (e.g., diabetes, heart disease, kidney dysfunction, chronic pain, migraine headache) that could lead to the complaint of insomnia, (3) there was no suspicion of narcolepsy, nocturnal myoclonus, or complaint of restless legs during intake interviews (Coates and Thoresen, 1980), and (4) during baseline recordings, subjects showed more than 30 min awake after sleep onset and/or 15 or more arousals during sleep. Also during baseline recordings, nasal thermistors, thoracic strain gauges, and recordings from the anterior tibialis muscles were used to verify that Subjects did not suffer from sleep apnea or nocturnal myoclonus.