Across India’s bustling cities, a crisis of staggering proportions is unfolding, largely unseen and uncared for by those who don’t wish to notice. As India strides toward modernization and ...

When Masoom Ali Shaikh arrived in Mumbai in 1974 as a young man from northern India, the patch of land where he set up shop was “just a creek with no proper road and garbage all around,” he said.

Dharavi is a square mile of corrugated iron, concrete blocks and plastic sheeting in the middle of Mumbai, crammed with humanity. With perhaps 1m residents, the slum is one of the world’s biggest. As ...