The network approach to urban studies can be differentiated from other approaches by its emphasis on the primacy of structures of interpersonal linkages, rather than on the classification of social units according to their individual characteristics. Network analysis is also a methodology for the investigation of these structures. Substantive issues related to interpersonal ties in the city, migration, resource allocation, neighborhood, and community are examined in terms of the network structures and processes that order and integrate urban activities. Finally, a view of the city itself as a network of networks is proposed. It is the organization of urban life by networks that makes the scale and diversity of the city a source of strength rather than of chaos, while it is precisely that scale and diversity which makes the existence of a complex and widely ramified network structure possible.