This study attempted to determine the prevalence of dissociative identity disorder in the general population. The Dissociative Experiences Scale (DES) was administered to 994 subjects in 500 homes who constituted a representative sample of the population of Sivas City, Turkey. The mean DES score was 6.7 +/- 6.1 (mean +/- SD). Of the 62 respondents who scored above 17 on the DES, 32 (51.6%) could be contacted during the second phase of the study, They were matched for age and gender with a group of respondents who scored below 10 on the scale, and the Dissociative Disorders Interview Schedule (DDIS) was then administered to both groups. Seventeen subjects (1.7%) received a diagnosis of dissociative disorder according to the structured interview. In the third phase, eight of 17 subjects who had a dissociative disorder on the structured interview could be contacted for a clinical evaluation. They were matched with a nondissociative control group and interviewed by a clinician blind to the structured interview diagnosis. Four of eight subjects were diagnosed clinically with dissociative identity disorder, yielding a minimum prevalence of 0.4%. Dissociative identity disorder is not rare in the general population. Self-rating instruments and structured interviews can be used successfully for screening these cases. Our data, derived from a population with no public awareness about dissociative identity disorder and no exposure to systematic psycho-therapy, suggest that dissociative identity disorder cannot be considered simply an iatrogenic artifact, a culture-bound syndrome, or a phenomenon induced by media influences, Copyright (C) 1999 by W.B. Saunders Company.