Urbanization causes changes in the water balance. Focusing on runoff, the aim of this report was to determine how both the magnitude and the form of this component change with urbanization. Also, solutions for decreasing the possible problems related to an increase in surface runoff were examined. Solutions were studied for both a general European situation and for the specific case of the Netherlands. Already after converting a forested area into agriculture, the runoff becomes more prominent, at the expense of evaporation and infiltration. When developing further into an urban area, its importance increases even more. In the last few years, various scientists have come up with suggestions of reducing the risks caused by increased runoff. Some examples are increasing the infiltration capacity or storing the excess water in cities. Considering the predicted future climate scenarios, water storage seems to be the best option. In the Netherlands, expanding the areas for water storage is the main subject of governmental research at the moment. On top of that, researchers advice to cooperate more between different stakeholders when considering water management. The main findings are thus that runoff increases with an increasing imperviousness of the surface, and the best solution to avoid problems caused by this enhanced amount of runoff seems to be the storage of excess water in cities. This solution is valid for both a general situation and in the Netherlands.