2. Chronotherapy:
This behavioral treatment consists of a gradual shift in sleep time in accordance with the patient's tendency. The changes recommended for different disorders are:
In Delayed Circadian Rhythm Disorder (DCR) a progressive delay of bedtime by 3 hours per day is prescribed, followed by strict maintenance of a regular bedtime hour once the desired schedule is achieved.

In
Advanced Circadian Rhythm Disorder (ACR) chronotherapy focuses on advancing bedtime by 2-3 hours per night over 1 week until a desired schedule is achieved.
For Bimodal Circadian Rhythm Disorder (BCR) and Non 24-hour Sleep/Wake Cycle the therapy is initiated based on the sleep pattern.