Clarence Stein, 1882–1975, American architect, b. New York City, studied architecture at Columbia and the École des Beaux-Arts. Stein worked in the office of Bertram Grosvenor Goodhue, where he assisted in the planning of the San Diego World's Fair (1915). Along with Lewis Mumford and Henry Wright, Stein was a founding member of the Regional Planning Association of America, a group instrumental in importing Ebenezer Howard's garden city idea from England to the United States. Stein and Wright collaborated on the design of Radburn, New Jersey (1928–32), a garden suburb noted for its superblock layout. Stein wrote Toward New Towns for America (1951).