Psychoanalysis finds its origins in the hypnotic treatment of a patient who suffered a major dissociative disorder, Anna O. Over time, psychoanalysis dissociated itself from hypnosis and the dissociative disorders, creating schisms so profound that it took nearly a century for such patients to become the subject of serious psychoanalytic consideration once more, and even longer for Freud’s misrepresentations of hypnosis to receive scholarly scrutiny. As dissociation and the dissociative disorders make their way back into the mainstream of mental health concerns, it is timely to offer a brief summary of the domain of dissociation, explore how dissociation and hypnosis became marginalized within psychoanalysis, and explore how restoring to psychoanalysis an appreciation of what has long been exiled can contribute to enhancing the treatment of dissociative disorders by the psychoanalytically oriented clinician. A novel recategorization of dissociative defenses is proposed.