The purpose of this study will be to redefine the nature and source of tolerance through an analysis of the complex patterns of interdependence that develop in urban environments. Some of the most crucial developments in this process include the following: 1) Increased need for interaction among diverse types of people, 2) symbols and other forms of commonality external to the individual, and 3) development of institutions and mechanisms for regulating such interaction and upholding such symbols. First, literatures on urban sociology and research on civil liberties are used to create an urbanism- tolerance paradigm. Short comings of urbanism are discussed through more detailed views of the composition of populations and the potential for subcultural development. I then argue that past efforts to explain tolerance have been biased by attitudinal measures of the extension of civil liberties. Review of the historic context of urbanism and tolerance show that toleration of differences, at the structural level, is quite prevalent and that tolerant behavior is, in fact, a way of life.