Eye movement desensitization and reprocessing (EMDR) is a specialized form of psychotherapy that is used almost exclusively for treating PTSD and its associated conditions, including depression. EMDR typically is integrated into a conventional psychotherapy regimen and is not used alone to treat PTSD.

The theory behind EMDR is that stimulated rapid eye movement may help in the psychological processing of trauma. It is thought that the day's events and our reactions to them are processed during REM sleep. In a controlled EMDR session, moving light is used to induce rapid eye movement.

Because it is a new method of treatment, only a relatively small number of patients have been treated with EMDR for PTSD. However, the EMDR Institute reports that there are more controlled studies of EMDR and its effects than of any other trauma treatment. The EMDR Institute states that an estimated 1,000,000 people had been treated by 1995, with varying degrees of improvement. Some, but not all, studies document improvement after relatively few interventions.