Peter Ravenscroft is a Research Associate at the University of Cambridge and a hydrogeologist with extensive international experience in Asia, Africa, the Caribbean and Europe. He spent more than 10 years working in Bangladesh, where his involvement in research into the extent and causes of arsenic pollution in that country became the basis for this book. He co-authored the first book on groundwater resources in Bangladesh. Hugh Brammer spent 22 years with FAO in East Pakistan/Bangladesh, first as a soil surveyor then as an agricultural development adviser. Following retirement, he was a visiting consultant for a further seven years, inter alia for the Bangladesh Flood Action Plan, and wrote seven books on Bangladesh's physical environment and agriculture. Keith Richards is a fluvial geomorphologist and Professor of Geography at the University of Cambridge. He has research interests and experience in catchment and river processes and their management in Europe, Central America, India, Africa and China, and has been Director of the Scott Polar Research Institute and a Vice President (Research) of the RGS-IBG. He has authored and edited several books, and published over 150 academic papers.