We have identified a need to draw together knowledge of physiochemical and biological aspects of pollution in tropical aquatic systems. This book results from this and we hope will assist in providing management strategies to protect these systems from pollution effects. In organising the book we have, as far as possible, attempted to cover the range of topics important in understanding pollution in tropical areas. Authors who are expert in their particular fields have been invited to contribute. We recognise that many topics remain uncovered but we hope will serve to assist in identifying these and stimulate interest in this area.