More than half of the world's population now lives in urban areas, and a billion of these urban dwellers reside in neighborhoods of entrenched disadvantage--neighborhoods that are characterized as slums. Slums are often seen as a debilitating and even subversive presence within society. In reality, though, it is public policies that are often at fault, not the people who live in these neighborhoods.

In this comprehensive global history, Alan Mayne explores the evolution and meaning of the word "slum," from its origins in London in the early nineteenth century to its use as a slur against...