Economic development policymakers are energetically devising strategies to return idle or abandoned industrial sites — so-called brownfields-to productive use. The most ardent proponents expect the benefits to be twofold. First, they believe brownfield redevelopment can help attract jobs back to the central cities, where unemployment runs high and where some popular notions of justice suggest that the wealth-generating activities of the past should not be a costly legacy to the nation's urban poor. Second, many argue that urban-oriented brownfield redevelopment policies are needed to offset the current biases toward greenfield development that tend to produce urban sprawl. Pristine greenfields are often cheaper to develop, but the regionwide effects of such development may be less beneficial as congestion, environmental degradation, and other growth-related problems can accompany spurts of development on the urban fringe.