 This is the Sahel, a desert region in Africa, where nuclear science is helping people to find clean water. Home to 135 million people, the Sahel often suffers from extreme drought. With the support of the IAIA, scientists from 13 countries in the Sahel were trained to use nuclear techniques to characterize groundwater. These countries need this kind of groundwater information to be able to manage their resource very well. With water being fresh and being usable for domestic purposes, then these people can have a healthier life, better agriculture. The focus of the study was on shared groundwater resources in five basins, which provide the main water supply for the region. The analysis of water samples using isotope hydrology confirmed large amounts of good quality groundwater. The project achieved a first broad overview of groundwater in the Sahel. So we have now a basic understanding of where is the groundwater, how much there is what is the quality. And now these countries can improve the management of their water resources. What we need to do now is to translate the science into policy and from then obviously to impact the everyday life of those millions of people who do not have adequate drinking water in the Sahel.