“By 2050, almost 70 percent of the world’s estimated 10 billion inhabitants—or more than the number of people living today—will be part of massive urban networks. … These staggering statistical trends are driving the evolution of the ‘megacity,’ defined as an urban agglomeration of more than 10 million people. Sixty years ago there were only two: New York/Newark and Tokyo. Today there are 22 such megacities—the majority in the developing countries of Asia, Africa, and Latin America—and by 2025 there will probably be 30 or more.”