Depersonalization is defined and the clinical characteristics of 9 patients presenting with Depersonalization Syndrome are discussed. The cases comprise 5 males and 4 females with an age range of 15-47 years, of which two-thirds presented with an acute onset of symptoms. The diagnosis is made on the patients' own descriptions of their symptoms. Criteria laid out by Ackner and ICD-9 are closely adhered to. The findings of the study are compared with those of Shorvon's 66 cases and similarities are found. Depersonalization symptoms described by Mayer-Gross are reviewed. That depersonalization itself appears to have an affective aspect and a somatic aspect is noted, and an explanation for both aspects is attempted. The resistance to various treatment is confirmed.