Harry Stack Sullivan is American psychiatrist born February 21, 1892 in Norwich, New York . He died January 14, 1949 in Paris, France. He received his medical degree in Chicago College of Medicine and Surgery in 1917. He headed from 1936 to 1947 the Washington School of Psychiatry.

Sullivan was a child of Irish immigrants and allegedly grew up in an anti-Catholic town. This resulted in social isolation which might have been the incitive for his later interest in psychiatry.

He developed a theory of psychiatry based on interpersonal relationships where cultural forces are largely responsible for mental illnesses. He extended the Freudian psychoanalysis to the treatment of patients with severe mental disorders, particularly schizophrenia.

Sullivan worked or taught to many well-known psychiatrists (e.g. Erik H. Erikson, Erich Fromm, Karen Horney). Although, well recognized by many he never acquired as much substantial reputation as many later did. He also founded the journal Psychiatry in 1937.

His writings include Conceptions of Modern Psychiatry (1947, repr. 1966); Interpersonal Theory of Psychiatry (ed. by H. S. Perry and M. L. Gawel, 1953, repr. 1968); Schizophrenia as a Human Process (1962, repr. 1974)