Psychiatrist, born in Kesswil, Switzerland. He studied medicine at Basel, and worked at the Burghölzli mental clinic in Zürich (1900-9). He met Freud in Vienna in 1907, became his leading collaborator, and was president of the International Psychoanalytic Association (1911-14). He became increasingly critical of Freud's approach, and Wandlungen und Symbole der Libido (1911-12, trans The Psychology of the Unconscious) caused a break in 1913. He then developed his own theories, which he called 'analytical psychology' to distinguish them from Freud's psychoanalysis and Adler's individual psychology. Jung's approach included a description of psychologcial types ('extraversion/introversion'); the exploration of the 'collective unconscious'; and the concept of the psyche as a 'self-regulating system' expressing itself in the process of 'individuation'. He held chairs at Basel and Zürich.