There is increasing interest in depersonalization disorder, in part because of the increased community awareness of the condition via the Internet. The disorder may be more prevalent than schizophrenia but is often misdiagnosed; hence, an update is timely.Recent research has included characterization of the nosology and phenomenology of the disorder, whereas emerging evidence demonstrates a neurophysiological dampening down in addition to psychological dampening in the face of emotional stimulation.Greater understanding of the clinical characteristics of this disorder will improve the reliability of diagnosis and aid the development of neurobiological and psychological models for empirical testing. Although response to current treatments has been disappointing, recent research has identified the basis for the development of new pharmacological and psychological treatments.