The Seven Challenges of Sustainable Cities

The departing point for this paper is that we do not know what a sustainable city is. The present situation is characterised be small demonstration projects and strategies for urban sustainable development that are not coherent. The modern city can be viewed as a complex technological system. The urban infrastructure, the buildings and their users interact in numerous and increasingly complex ways. The paper analyses some of the challenges cities meet in their quest for sustainability: Lack of awareness and ethics; Lack of tools for decision making; Lack of models for sustainable urban management; Lack of diffusion of innovations; The momentum of existing infrastructure; Counteracting trends in the development of modern society and the need for reinventing planning.