Abstract: Jung claimed that Richard Wilhelm, whose masterful translations of Chinese wisdom literature into a European language (German) and thence into Western consciousness have brought Chinese modes of thinking to so many, was one of the most important influences on his own life and work. The contacts between the two men, which took place from the early 1920's until Wilhelm's death in 1930, were few but intense and for Jung decisive in several ways. Wilhelm's translations of the I Ching and The Secret of the Golden Flower opened new avenues for Jung that had far-reaching consequences on his research and writing after 1930. The latter opened the door to the study of alchemy as a key to the archetypal process of individuation as rooted in the collective unconscious. ‘Synchronicity’ is a term that grew out of his contact with Chinese thought, in particular with the I Ching. From his contact with Chinese thought, additionally, he received confirmation of the view, independently arrived at, that adult psychological development is not linear but rather circular and spiral-like. The letters between Jung and Wilhelm illuminate the great importance Jung ascribed to Wilhelm's contribution toward bridging East and West and the potential value of Chinese philosophy for psychotherapy.