For the first time in history, more than half the world's people live in cities, an extraordinary change in circumstances for human beings and the natural environment. Coming to terms with an urban world requires an understanding of the complex relationships between cities and natural ecosystems. "City" and the "Environment" are not mutually exclusive terms. Facing urban conditions in the 21st century requires an understanding of the interaction between social, cultural, economic, political, and environmental factors. Christopher Boone and Ali Modarres explore the city, its environment, and the role humans play in shaping the meaning and condition of both. In doing so, they engage the reader in an exploratory discourse on the urban environment.