Cities are thought to have first formed 6,000 years ago in what is now Iraq. By 2050, two-thirds of us will live in them. What does the future hold for our cities? Should we live in dense urban areas with public transit and walkable amenities? In sprawling suburbs created by our infatuation with the car? In high-rises, like those dotting urban districts across China? Is there room for all of it? For this special issue, we sent photographers across the globe to document how cities work – and don’t.

In northern Uganda, a great experiment is under way. In an area more than twice the size of Paris, an industrial skyline of water and cell towers hovers over sturdy mud huts and small farm plots. Schools and health centers are built from brick and fitted with glass windows. Taps run freshwater, and small solar panels power streetlights, as well as the radios blasting music from barbershops, televisions airing soccer matches in community halls, and cell phones snaking from charging stations in shops. Festivals, fashion shows and even a beauty pageant have been held.

This is Bidibidi. With a quarter million people living in its many villages, it’s the second largest refugee settlement in the world. Can a refugee crisis birth a permanent city that endures even if the refugees return home? Join now ›

Rats are our shadow selves. We live on the surface of the city; they generally live below. We mostly work by day; they mostly work by night. And from Seattle to Buenos Aires, urban rat populations are rising—as much as 15 to 20 percent in the past decade, according to one expert.

Of all the animals that thrive in our world—pigeons, mice, sparrows, spiders—we feel strongest about rats. They have a reputation for being filthy and sneaky. They’re seen as signs of urban decay and carriers of pestilence. They inspire fear and disgust. People hate rats. But do they deserve it? After all, rats help keep us from wallowing in our own filth: If we can’t love them for it, respect and a little acceptance would be a healthy step.

And until cities change how they deal with their trash, the rats are winning. Join now ›

Today’s city planners face a big challenge: fighting the sprawl that has disconnected communities and forced people into cars to navigate from home to work to shopping. In the U.S., sprawl happened for reasons that made it seem like a good idea at the time. Millions of soldiers had come home from World War II to overcrowded, run-down cities; their new families needed a place to live. Driving to the suburbs felt liberating and modern. In China, after the cultural revolution, sprawl happened for good reasons too. Just as with American suburbs, which helped realize millions of American dreams, the results are great, to a degree. The average Chinese family now has 360 square feet of space per person, four times the average of two decades ago. But the spaces between the buildings are uninviting, and people don’t use them.

As one architect said, “If you really want to affect environmental outcomes and social outcomes, it’s not shaping a single building that matters, it’s shaping a community.” Join now ›

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