Introduction

Abstract

Cities are focal points for the activities of societies. They are centers of employment, commerce, education, culture, and social and political interaction. They also impose significant demands for civil infrastructure needed to support social and economic activities and a suitable quality of life. The challenges in providing this infrastructure are magnified in very large cities – megacities, having populations of eight million or more inhabitants (Guest 1994) – and especially in the rapidly growing megacities found in developing countries worldwide.