Becoming a successful city involves achieving a high investment/high return equilibrium, just as much as it does for the most successful businesses. Success in the open knowledge driven global economy requires places to be truly distinctive, appealing and productive. Just as firms must innovate and invest to succeed, cities have to adjust, reinvent, and differentiate themselves. They have to change the old patterns of land and resource use, and connect assets with opportunities in new ways and over new spaces. They must modernise infrastructure and build up human capital. This can have positive impacts on entrepreneurship, innovation, skills, and other factors of growth. But this involves adjustment costs, in the form of investment to re-engineer the city for the new economic functions and flows that it must facilitate. It can take 30-50 years of re-investment to fully recalibrate a city from the industrial mode to the knowledge mode...