Psychological integration occupies a central and contested position across the depth-psychology corpus, functioning simultaneously as clinical goal, developmental ideal, and ontological principle. The term’s valence shifts markedly depending on theoretical home: in trauma-oriented frameworks — notably those of Janet, van der Hart, Ogden, and Courtois — integration names the restoration of coherent personality organization disrupted by dissociation, requiring synthesis, realization, and the overcoming of phobic avoidance of traumatic memory. In Daniel Siegel’s interpersonal neurobiology, integration becomes the foundational mechanism of mental health itself, defined precisely as the linkage of differentiated elements within and between minds, producing coherence, flexibility, and narrative continuity. Jung and his inheritors — Hillman, von Franz, Edinger, Vaughan-Lee — frame integration less as repair than as individuation: the assimilation of shadow, the reconciliation of opposing psychic functions, and ultimately the approach toward wholeness symbolized by the Self. Alexander’s dislocation theory extends the concept outward into the social field, where ‘psychosocial integration’ denotes the irreducible human need to belong while remaining autonomous. Welwood adds a further complication, distinguishing psychological integration from spiritual actualization and cautioning that the former does not guarantee the latter. The key tension running through the corpus is whether integration is essentially a process of recovery from fragmentation or a lifelong telos of increasing complexity and coherence — a clinical task or a philosophical aspiration.