These five cities have come up with unique ways to fight back.

As bleak housing projects darkened city skies, urban theorist Jane Jacobs sang the virtues of a thriving neighborhood in her 1961 landmark book, “The Life and Death of Great American Cities.” Within its pages, “She pointed out a fact to which many planners and administrators had been indifferent — that a neighborhood is not just a collection of buildings but a tissue of social relations and a cluster of warm personal sentiments, associated with the familiar faces of the doctor and the priest, the butcher and the baker and the candle-stick maker, not least with the idea of ‘home,’” a reviewer wrote at the time. “The sidewalk, the street, and the neighborhood, in all their higgledy-piggledy unplanned casualness are the very core of urban life.”

But what happens when a casual stroll down the sidewalk yields more encounters with overgrown lots and shuttered storefronts than neighbors? How can you rejuvenate a feeling of urbanism when only one house on a block’s inhabited?

In these five cities, the remaining residents are battling blight, saving their homes from becoming ghost towns.

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