This book contains the keynote address, 52 papers presented at the Fifth International Conference on Water Pollution Modelling, Measuring and Prediction, which was held on the island of Lemnos, Greece, May 24-26, 1999, and 3 additional papers. The conference was jointly organized by the Wessex Institute of Technology, Southampton, UK, and the Division of Hydraulics and Environmental Engineering of Aristotle University of Thessaloniki, Greece. The book focuses on recent developments in the handling of water pollution and includes contributes from international academic, government and industrial researchers working in a broad variety of fields, from fluid mechanics to computer sciences to biology and chemistry to remote sensing. The series of conferences, held biennially since 1991, fosters discussion among international researchers working in the many different fields that touch on water pollution: fluid mechanics, oceanography, hydrology, mathematics, computer sciences, biology, chemistry, and many others. Participants at each conference have come from academia, government, science, and industry.