After their basic training in EMDR, many EMDR therapists realize that the EMDR standard protocol, and even the AIP model alone, may not be sufficient to conceptualize and treat cases of severe traumatization. Often, such cases include a history of chronic or repeated experiences of physical or sexual violence, neglect, psychological violence, war, etc. Learn more about dissociative identity disorder (DID), Ego state theory and therapy (EST), and theory of the structural dissociation of the personality (TSDP) in this article from the Fall 2021 issue of Go With That magazine by Olivier Piedfort-Marin, Ph.D.