When it rains, what happens to the water? How do floods occur? What impact does climate change have on water and how do humans influence water systems? In a doctoral programme funded by the FWF, interdisciplinary research teams led by hydrologist Günter Blöschl from the Vienna University of Technology (TU Wien) discuss a variety of aspects relating to the planet's most valuable resource. The issues range from water management to water use, water protection and water quality.