[Multiple personalities in a 15-year-old girl].

This case report is about a 15-year-old girl, who had multiple personalities. Dissociative identity disorder (DID) is a complex disorder characterised by two or more distinct identities or dissociated personalities. These states or identities alternately control the person's behaviour, accompanied by memory impairment of important information. The diagnosis is relatively uncommon in clinical practice in Denmark and is associated with controversy regarding its validity. The growing empirical research on DID supports its validity as a psychiatric disorder, but the disorder may however suffer from under- or misdiagnosis.