Why Big Cities Matter in the Developing World

Half the world's population lives in cities today, a figure that will increase to 70 percent by 2050. In that same time period, McKinsey Global Institute projects that the economic output of the 600 largest cities and metro areas is projected to grow $30 trillion, accounting for two-thirds of all global growth.

Economists and urbanists have long noted the connection between urbanization and economic development. As Harvard University economist Edward Glaeser points out, “if you compare countries that are more than 50 percent urbanized with countries that are less than 50 percent urbanized," he writes, "incomes are five times higher in the more urbanized countries and infant mortality rates are less than a third in the more urbanized countries.”