The establishment of the modern corporate office building was the greatest achievement of American architecture after World War II. Yet, this American accomplishment was misinterpreted as the triumph of International Style Modernism. Instead, Architecture, Advertising and Corporations 1929-1959 studies the paramount role played by corporate clients as a new contribution to a body of work that offers enriched and complicated accounts of modern architecture. The dissertation details four case studies from consecutive decades in the mid-twentieth century. They include, The PSFS Building, designed by Howe and Lescaze, The Johnson Wax Building designed by Frank Lloyd Wright, Lever House designed by SOM, and The Reynolds Metals Sales Headquarters designed by Minoru Yamasaki. The cross-disciplinary study presented here, shows that the modern office building was in fact, influenced by corporate views of architecture as advertising. Architecture, advertising, and corporate culture are interwoven in the story of American corporate architecture of the twentieth century, fulfilling the visions of both their clients and their architects.