Mumbai and other Indian cities enact labor restrictions to stem an influx of poor migrant workers.
Crews once bulldozed thousands of slum homes in Mumbai, a metropolitan region of about 16 million people in India. Santosh Thorat sees a better way: Help residents fix them up.
By 2050, 7 out of 10 people will live in megacities, offering the benefits of concentrated living but also some of the biggest public-works challenges in human history.
A UN-Habitat report on the state of the world's cities found that 227 million people have moved out of urban slum conditions over the past decade. Half the world's population now lives in cities.