Laurence Smith is Senior Lecturer in the Centre for Development, Environment and Policy, School of Oriental and African Studies, University of London, UK.Keith Porter is Adjunct Professor at Cornell Law School and the former Director of the Water Resources Institute, Cornell University, Ithaca, New York state, USA.Kevin Hiscock is a Reader in the School of Environmental Sciences, University of East Anglia, UK and author of a standard textbook on Hydrogeology.Mary Jane Porter is a consultant in watershed management and was previously at the Water Resources Institute, Cornell University, USA.David Benson is a lecturer in the School of Environmental Sciences, University of East Anglia, UK.