In 2008, Matthew Desmond moved into a trailer park on the southern edge of Milwaukee, where most everyone was white. A few months later, he relocated to a rooming house on Milwaukee’s heavily African American north side. There, he lived with a security guard who worked at the trailer park. Desmond was a budding sociologist pursuing his graduate degree at the University of Wisconsin in Madison, an hour west of Milwaukee. His aim was to better understand life at the hardscrabble margins of the housing-rental market.

Desmond is white. His neighbors at the trailer park thought he was crazy to move