These are boom times for social histories of Mexico City's working people. Within the past decade, nearly a dozen major studies have appeared in the United States and Mexico exploring the nineteenth- and twentieth-century worlds of artisans, workers, prostitutes, and other members of the urban “dangerous classes.” This new generation of scholarship has moved the study of Mexican working people's history away from its timeworn emphasis on the official politics of labor unions and the concomitant institutional analysis of inter-union alliances, schisms, and pact making with the state. Instead, the recent work has begun to sketch in a portrait of the everyday lives, political struggles, and cultural perspectives of the unionized and nonunionized popular classes in Mexico's capital. John Lear's history of Mexico City's working people in the late nineteenth and early twentieth centuries represents a major contribution to this literature, thanks in part to its chronological breadth and ambitious scope.