Paul Whitehead is Professor of Water Science at the University of Oxford (https://www.geog.ox.ac.uk/staff/pwhitehead.html) and Professor Emeritus from Reading University. He has over 35 years’ experience of research on water quality and pollution issues, and has a special interest in modelling, including the development and application of dynamic, stochastic, planning and forecasting models. He has been director of the £11 million NERC Macronutrient Cycles Programme and has been successful in running over 50 projects funded by NERC, EPSRC, ESRC, EU, EA and a range of Government Departments such as DEFRA, FCOD and DTI. Professor Whitehead has served on several senior UK Research Council committees and he has also been an environmental research advisor to the UK Government, the EU, Belgium and Romania, and he has also worked in Nepal, Thailand, India, China, Brazil, Australia, Bangladesh and the USA. He has published widely, with over 220 papers in the refereed literature, as well as being guest speaker at a wide range of conferences and meetings. He attended the first Earth Summit in Rio and the 26th in Glasgow. He has developed the Integrated Catchment Model (INCA) for flow and water quality and applied the model to over 70 river systems around the world, evaluating impacts of Climate Change, Pollution Control, Land Use Change and Population Change.