It was only forty years ago that the Seine River was declared ‘dead’. Levels of pollution from industry and agriculture were dangerously high. Native fish had disappeared, plant life was dying, and the water was unsafe for swimming. Today, however, the river and its surroundings have been rehabilitated. The city of Paris even organizes fishing contests on summer afternoons. This dramatic change began with the recognition in 1964 of six river basins as the natural hydrographic units in France and the creation of six water agencies to manage them accordingly. Problems remain, especially nitrate pollution from fertilizers and the continuing disappearance of wetlands, but the case study presented here shows that the application of modern technology, a sound tax base and political will on several levels can go a long way towards reversing some of the neglect of the past.