The Research Training Group (RTG) “Integrated Hydrosystem Modelling” at the German Universities of Tübingen, Hohenheim, and Stuttgart targets at developing and applying numerical models of flow and reactive solute transport in coupled hydrosystems comprising of land-surface and subsurface compartments. These models are needed to assess the impacts of environmental change on water quantity and quality at catchment scale. The RTG offers a structured PhD program at the German partner universities with joint international training and supervision.