Preface

Since around 1960, the speed, scale, scope and complexity of urban transformation processes of the developing world have become a formidable task to manage. It is now undoubtedly one of the most important challenges facing humankind. The urban population of the world never exceeded 7% until about 1800. The whole rural/urban dynamics was completely changed, especially in the developed word, by the Industrial Revolution. At present, nearly 75% of the inhabitants in the Western world live in urban areas.