From a demographic point of view, more than 9 billion people are expected to live on planet earth in 2050, two-thirds of them in cities. Actually, the entire anticipated population increase is to take place in urban areas, with over 90 percent in Africa, Asia, and Latin American and the Caribbean ; so, global urbanization has long since shifted to developing countries and emerging economies. Approximately 2.7 billion people live in urban agglomerations in developing and emerging economies today; in 2030, that number will rise to 3.9 billion – and reach 5.1 billion in 2050. Around 95 percent of this urban momentum is going to take place in metropolitan regions. Established mega regions like Sao Paulo or Mumbai, as well as urban agglomerations composed of rapidly growing small and medium-sized cities will become the key living and economic spaces of the urban millennium.