The development of exhibition buildings is inseparable from international world expositions. Historian Nikolaus Pevsner demonstrated that the 20th-century exhibition building has 19th-century origins, with stylistic and programmatic links to the conservatory and market hall. Expositions are brief events usually lasting only one season, although they may consume up to ten years of planning effort. The buildings serve to display the innovative technological, industrial, economic, scientific, and cultural ideas of the participating nations. The Bureau International des Expositions (BIE), which administers these events, selects a timely theme that serves as a catalyst for each event. Themes provide an informational and organizing principle that guides much of what is designed and constructed. Themes have been celebratory, such as “The Age of Discovery” for Expo ‘92 in Seville, marked by the 500-year anniversary of the sailing of Columbus to the New World, or more frequently address a globa...