Dissociation is a “the disruption of the normal integrative processes of consciousness, perception, memory, and identity that define selfhood.” Dissociative identity disorder it is the most complex of the Dissociative Disorders. This mental disorder is included in both the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) , and the ICD-10. It has been recognized “for centuries” and first became a separate diagnosis in the DSM-III as “multiple personality disorder.”
The DSM-5 Guidebook provides this helpful description
Individuals with dissociative identity disorder may first present with symptoms of emotional and behavioral turmoil. Some may notice memory gaps and incidents of out-of-character behavior. These systems result from different “alters,” or alternative identities, controlling an individual’s behavior for varying lengths of time. Switches have been observed in stressful situations, disputes among alters, and other psychological conflicts.
 Waseem M. “Dissociative Identity Disorder”, Medscape. (2014).
 DSM-5 Guidebook: The Essential Companion to the Diagnostic and Statistical Manual of Mental Disorders. ISBN 9781585624652.p 192-193
- International Classification of Diseases (ICD-10)
- DID criteria from DSM-5
- Dissociation: What is it and how to help (taikonenfea. wordpress.com)
- What life is really like with DID (diddispatches.wordpress.com)
- Trauma and Dissociation Frequently asked questions International Society for the Study of Trauma and Dissociation
- Evidence that Dissociative Identity Disorder (Multiple Personality Disorder or MPD) is caused by Childhood Trauma (eassurvey.wordpress.com)
- Social Worker Living Successfullyy with DID (socialwork.carrer) (traumadissociation.wordpress.com)
- DSM II: History of multiple personalities (traumadissociation.wordpress.com)