Early in the history of studies on the release of ACTH by stress there were indications that ACTH might be released by multiple factors. But the neurohumoral theory, as formulated by G. W. Harris, suggested that every hypophysial hormone had its unique hypothalamic controlling agent and a search for the unique ACTH-releasing hormone went on for about 20 years. This review reexamines the case for multiple releasers of ACTH
