Book excerpt: Much of today's heated academic discussion about "social capital" is either theoretical in nature or revolves around national survey data, neither of which adequately explains the specific social networks that actually sustain life in cities. This is the first book about social capital that both spans a broad range of social contexts and time periods and focuses on a single city, Philadelphia. Contributors examine such subjects as voter behavior, education, neighborhood life, church participation, park advocacy, and political activism. The wide scope of the book reflects its concern for comprehending the uniqueness and diversity of urban social networks.Moving beyond typical definitions, the original essays collected here utilize case studies to demonstrate how social capital is nested in larger structures of power and cannot be appreciated without an understanding of context. Arguing that urban society is "social capital writ large," contributors complicate and deepen our knowledge of a crucial concept and its fruitful applications.