The world has never been more urban than it is now, and this trend isn’t expected to slow down anytime soon. By 2050, the world will have grown by 2.5 billion additional urban dwellers, with almost all of this growth occurring in cities in the developing world. According to 2014’s Better Growth, Better Climatereport, the world will need to invest about $50 trillion in infrastructure every year for 15 years to keep up with demand. India, for example, is estimated to need 350 to 400 kilometers of new metro and subway lines every year—20 times what it’s achieved in the past decade. While this is a tall order, it also presents great opportunities to improve our cities. To ensure that these investments result in communities that are productive, livable and sustainable, we have to change how we build, manage, and use our cities.
This means changing current patterns of land use, transportation, and lifestyles. Cities across the globe have already implemented many innovative solutions to become more sustainable and improve quality of life. But how do we go from individual, isolated successes to real change at a global scale?