Psychic dissociation occupies a foundational position in the depth-psychological corpus, functioning simultaneously as a clinical symptom, a metapsychological principle, and a structural datum of the psyche itself. Jung’s early formulation, elaborated through his complex theory, established dissociation not merely as pathological fragmentation but as an inherent feature of psychic organization: every complex, he maintained, carries the character of a ‘splinter personality,’ and being ‘in complex’ already constitutes a mild dissociative state. The traumatic intensification of this process—wherein a complex achieves full autonomy, tyrannically overriding conscious will—became the ground upon which later theorists built. Kalsched’s archetypal-defensive reading cast dissociation as the psyche’s self-protective measure against unbearable pain, animating persecutory inner figures that simultaneously preserve and imprison the personal spirit. Van der Hart, Nijenhuis, and collaborators formalized these insights into the structural dissociation of the personality model, distinguishing primary, secondary, and tertiary dissociation according to the number and complexity of Apparently Normal and Emotional Parts involved. Nijenhuis extended the field further by demonstrating that dissociation encompasses not only psychological but somatoform registers. Hollis and Stein, writing from closer proximity to the Jungian tradition, emphasize the spectrum from quotidian ego-complex states to multiple personality disorder. The central tension across the corpus is whether dissociation is a defense to be respected, a deficit to be integrated, or a structural fact of the plural psyche requiring therapeutic acknowledgment before resolution.