Depersonalization/Derealization Disorder (DSM-V) or depersonalization-derealization syndrome (ICD-10) is a disorder in which the patient complains of experiences of unreality, detachment, or being an outside ob­server with respect to one’s thoughts, feelings, sensations, body, or actions (depersonalization), or of experiencing unreality or detachment with respect to their surround­ings (derealization). Symptoms may occur as part of a diagnosable schizophrenic, depressive, phobic, or obsessive-compulsive disorder. In such cases the diagnosis should be that of the main disorder.