Procter & Gamble Co., Cincinnati
In 1931, when Procter & Gamble had a one-page memo rule, McElroy wrote a three-pager that led to P&G's legendary brand-manager system and fostered intra-P&G brand rivalries. He later put the company into radio's daytime soap opera schedules, had P&G produce soaps for daytime TV and, with Howard Morgens (who succeeded him as ad manager), moved P&G into Sunday supplements and contest promotions. McElroy started at P&G in 1925 as an ad department mail clerk, became VP-advertising in 1943, then president in 1948. He also became the first adman to serve as a U.S. cabinet officer with his appointment as Dwight Eisenhower's secretary of defense (1957-60). McElroy was P&G's executive committee chairman at the time of his death.