ABSTRACT
It has been our thesis throughout this book that green cities are already beginning to emerge. Their further development will need a lot of help, because this welcome emergence now needs to move from experiment to mainstream. The avoidance of catastrophic climate change is not a matter of choice. It is an imperative. Green cities are simply necessary if the human species is to have a long-term future in anything like the environmental abundance with which humanity at large is now fortunately surrounded. It is worth remembering that it is not lack of abundance that is the cause of poverty; it is the inability or unwillingness to share it fairly among the Earth's citizens.
