<p>At century¿s close, American social scientists, policy analysts, philanthropists and politicians became obsessed with a fearsome and mysterious new group said to be ravaging the ghetto: the urban ¿underclass.¿ Soon the scarecrow category and its demonic imagery were exported to the United Kingdom and continental Europe and agitated the international study of exclusion in the postindustrial metropolis.</p><p>In this punchy book, Lo¿Wacquant retraces the invention and metamorphoses of this racialized folk devil, from the structural conception of Swedish economist Gunnar Myrdal to the behavioral notion of Washington think-tank experts to the neo-ecological formulation of sociologist William Julius Wilson. He uncovers the springs of the sudden irruption, accelerated circulation, and abrupt evaporation of the ¿underclass¿ from public debate, and reflects on the implications for the social epistemology of urban marginality. What accounts for the ¿lemming effect¿ that drew a generation of