Within the German-Vietnamese joint research project “Integrated Water Resources Management Vietnam”, Planning and Decision Support Tools on a regional scale are being developed. A Water Balance Tool is utilized to calculate and assess water demands and compares these with the quantity of water resources to identify surpluses or deficits. The sensitivity of water resources and the contamination potential are combined to display water quality aspects within a Contamination Risk Tool. A resulting evaluation is carried out with a Ranking Tool. It identifies areas with high priority need for action. The Planning and Decision Support Tools are being discussed with Vietnamese institutions and authorities.