This is well researched and written and focused on key issues central to building a sustainable culture. The neglected issue of population density is most prominent, but the author also covers many other related issues and debunks many widely held myths about sustainability, such as the high relative priority we currently give to recycling, mass transit and various high-tech schemes for salvation. Owen maintains that Manhattan's population density is in part an accident due to a favorable geography. Some more discussion of how to retrofit existing urban centers to emulate Manhattan, by design, would have also been useful.