Non-24-hour sleep-wake disorder (N24SWD) is one of several chronic circadian rhythm sleep-wake disorders (CRSWDs). It is defined as progressive daily shifts in sleep onset and wake times. It mainly affects sight-impaired persons, is relatively rare in sighted patients, and is difficult to treat, with no guidelines. We report a case of N24SWD in a sighted young man who complained of alternating severe insomnia and excessive sleepiness, with a sleep agenda and actigraphic data showing a daily delay of approximately 2 hours. A novel therapy by total sleep deprivation followed by a combination of morning light therapy and nocturnal melatonin administration was efficient in stopping his free-running sleep-wake pattern both immediately and in the long term. The treatment combination for 6 months resulted in stable circadian entrainment to a 24-hour cycle. Compliance with chronotherapy was maintained over the course of follow up.