Multiple personality disorder, or MPD, is a mental disturbance classified as one of the dissociativedisorders in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders. It has been renamed dissociative identity disorder (DID). MPD or DID is defined as a condition in which "two or more distinct identities or personality states" alternate in controlling the patient's consciousness and behavior. Note: "Split personality" is not an accurate term for DID and should not be used as a synonym for schizophrenia.