The United Nations Brundtland Report defines sustainable development as one "that meets the needs of the present without compromising the ability of future generations to meet their own needs." Embedded in this concept of sustainable development are the needs of the world's poor as well as the limits of environmental technology and social organizations to meet these needs. Urban centers, home to the majority of world's population, are hubs of sustainability innovations. However there are major differences among how these sustainability issues are addressed in the Global North and South....