Insomnia is a common health complaint that produces a significant impairment in quality of life and involves difficulty in initiating sleep, maintaining sleep, waking too early, non-restorative sleep, and daytime functional deficits. Insomnia is associated with a disturbance in one or more of the three systems that regulate sleep: homeostatic, circadian and arousal. A disturbance may result from genetic/dispositional issues, from acute life events, from habitual behaviors and attitudes, or from any combination of these three types of issues. A number of treatment methods have been developed that use behavior modification and cognitive restructuring to facilitate homeostatic and circadian mechanisms of sleep, and to reduce arousal during bedtime. These methods actively engage the patient to implement life style changes, attitudes and beliefs that promote sleep.