William Allen Horning (November 9, 1904 – March 2, 1959) was an American two-time Academy Award winner. He was married to Esther Montgomery until his death. Together they had three sons. He joined Metro-Goldwyn-Mayer in 1931 as a draftsman and became an assistant to the studio's supervising art director Cedric Gibbons in 1936. Together with Gibbons, he received his first Academy Award nomination in 1937 for Best Art Direction for Conquest. Two years later, he received another nomination for The Wizard of Oz. He waited 12 years for his next nomination for Quo Vadis.