Apparatus and methods for treating psychiatric disorders, mood disorders and circadian rhythm disorders with a multi-stage light protocol are disclosed. The presently disclosed multi-stage light protocol provides a synergistic treatment including up to 4 types of therapies: bright light therapy, extended sleep deprivation therapy, dawn simulation therapy and short to medium wavelength light therapy. According to some embodiments, the first stage of the protocol includes a first time window of 20 minutes during which, for a majority of the time, the light intensity is between 50 lux and 2000 lux. According to some embodiments, the second stage of the protocol includes a second time window of at least 90 minutes during which, for every 10 minute period within the second time window, for a majority of the time, the light intensity is exceeds 100 lux. According to some embodiments, the third stage of the protocol includes a third time window of 60 minutes during which, for a majority of the time, the light intensity exceeds 2000 lux In some embodiments, the light is provided by apparatus including a plurality of LEDs. Typically, the light includes white light having a broad spectrum. In some embodiments, the light further includes light having a medium wavelength, for example, wavelengths between 520 nm and 535 nm.