Otto Rank was an Austrian psychoanalyst, writer, and philosopher. Born in Vienna, he was one of Sigmund Freud's closest colleagues for 20 years, a prolific writer on psychoanalytic themes, editor of the two leading analytic journals of the era, managing director of Freud's publishing house, and a creative theorist and therapist. In 1926, Rank left Vienna for Paris and, for the remainder of his life, led a successful career as a lecturer, writer, and therapist in France and the United States.

Sigmund Freud was an Austrian neurologist and the founder of psychoanalysis, a clinical method for evaluating and treating pathologies seen as originating from conflicts in the psyche, through dialogue between patient and psychoanalyst, and the distinctive theory of mind and human agency derived from it.