As older cities and towns retooled to accommodate post-industrialism, cultural districts have become popular strategies to promote tourism, revive downtowns, revitalize neighborhoods, and generally boost the local economy. While entertainment centers are hardly new to urban life, the cultural district as economic stimulus has become increasingly standard equipment in the planners’ toolbox. The typical district is “a well-recognized, labeled, mixed-use area of a city in which a high concentration of cultural facilities serves as the anchor or attraction.” Thus the cultural district is a strategy for simulating arts “consumption” and “event-related spending”, but planning largely ignores the production needs of artists and cultural providers. Generally, local government takes the initiative to define and create a cultural district through planning, legislation, and fiscal policy. Over 100 communities across the U.S. have planned cultural districts. The widespread practice of using of older, top-down models of urban policy, however, does not recognize the need to link cultural strategies with new urban realities and new models of social policy. This paper draws on SIAP's research on metropolitan Philadelphia to look at an alternative approach—that is, the dynamics of arts agglomeration or what the authors call "natural" cultural districts.