It is impossible to discuss national competitiveness without considering cities and the regions they anchor. Cities are transportation hubs, centers of commercial exchange, and the locus of lives. They thrive by the ways they connect to the world. Demographic changes in recent years—such as the decreasing popularity of cars and increasing urban populations—have implications for 21st century transportation and infrastructure. This is apparent in the case of Chicago, a global city in the vanguard of change. This paper focuses on five major 21st century transportation and infrastructure projects in Chicago: rail decongestion; airport modernization; mass transit modernization; a complete streets plan; and an infrastructure trust as a financing innovation. It also discusses leadership by Mayor Rahm Emanuel to create an integrated strategy that includes technology and education, and how he executes on it.