During the past decade many countries in the world have experienced droughts, with severe impacts on water urban supply systems. Because droughts are natural phenomena, water utilities must design and implement drought management plans. This topic was selected for the International Course on Drought Management Planning in Water Supply Systems, which took place in Valencia, Spain, on 9-12 December 1997, and was hosted by the Universidad Internacional Menéndez y Pelayo (UIMP). The contributions in this book have been carefully selected and presented in four sections: Introduction Water Supply Systems Modernization Drought Management in an Urban Context Practical Cases (Israel, USA, Italy, Spain) To achieve a well-balanced approach, authors were invited from academia as well as from consultancies and water utilities, and have wide experience in the subject. The book is mainly aimed at water supply engineers, working in utilities and consultancies.