Switzerland is the primary “watershed of Europe.” The Swiss Alps feeds all major Central European rivers including the Rhône, Danube, Rhine and Po. The country also plays a very active international role in environmental affairs since many multinational organizations such as the United Nations, the International Union for Conservation of Nature and Natural Resources (IUCN) and the Ramsar Convention are based in Switzerland. In the present paper we give a brief overview of the water policy of Switzerland and provide selected examples of the state and trends of the water environment. The most fundamental principles in water management were formulated in the Water Protection Law in 1991 and subsequently updated in 1991. In it, the protection of groundwater and the maintenance of residual flow in rivers and streams were manifested. Ground water supplies 80 % of the total water consumption of the human population. Local authorities identify groundwater protection areas, and unpolluted wastewater such as storm water is also used to recharge the aquifer. Furthermore, minimum residual flows are calculated to maintain the ecological integrity of rivers and streams. Finally, we compare the Swiss situation with the water conservation policy in Japan.