Contemplative Union designates, within the depth-psychology corpus, the experiential apex of mystical praxis: that state in which the practitioner’s individual consciousness is drawn into intimate, transformative contact with the divine ground, the One, or the Self. The corpus maps this territory across strikingly divergent traditions. In the Evagrian and Philokalic streams, contemplative union emerges as the culmination of a triadic ascent through ascetic purification, natural contemplation, and finally the theologia of the Blessed Trinity — a movement described in Evagrius as issuing in ‘essential knowledge’ (gnōsis ousiōdēs) that is experimental rather than conceptual. The Sufi trajectory, mediated chiefly through Henry Corbin’s reading of Ibn ‘Arabī, reframes union as unio sympathetica — a dialectical, bilateral passion in which Lover and Beloved mutually constitute one another’s divinity, foreclosing simple absorption in favour of an irreducible bi-unity. The Neoplatonic lineage, traced by Sharpe and Ure through Plotinus to Iamblichus, identifies a fault line: where Plotinus affirmed contemplative union with the One as philosophy’s highest achievement, Iamblichus held human nature too body-bound to attain it without theurgic rite. Jung translates the problematic into analytical terms, reading Eastern samādhi and the at-one-ment of the Trikāya as approximations of conscious encounter with the unconscious One Mind, while insisting the ego-residue renders complete union epistemologically impossible. The entry thus discloses a field shaped by the perennial tension between identity and distinction, dissolution and transformation.