The article lists the diverse occurrences in Freud's work where the presence of the case history known under the name of “Little Hans”, the analysis of a phobia in a five-year-old boy, is identifiable, sometimes cited explicitly, sometimes simply mentioned or cited in the footnotes. Freud was struck by this child whose parents he knew; the boy's father took part in the Wednesday meetings and his mother had been his patient. A reading of Freud's work reveals the regular occurrence of references concerning him as if the treatment of this child and the theory that he developed out of it had preoccupied him throughout his writings up until his last work. Moreover, he had the opportunity of meeting the child again when he was an adult and, in 1972, Herbert Graf (his real name) left us a moving and rare account of the evolution of an analysis.