During World War I he served as an ensign in the U.S. Navy, where he received an excellent technical education. After the war, Fuller worked for a Chicago construction firm and experimented with new building methods. In 1927, having decided to devote his time to technological inventions, he made a prefabricated house designed to hang from a central mast. Later inventions include a new worldmap projection constructed of six squares and eight triangles that had many of the advantages of a globe (1942). His geodesic dome, perfected in 1947, is perhaps the most significant structural innovation of the 20th century. Although Fuller had no architect's license or college degree, he was made the official architect for the U.S. pavilion, a transparent geodesic dome, at the 1967 World's Fair in Montreal (Expo 67). After 1959 Fuller was research professor in "design science" at Southern Illinois University.