A study including 6 prealpine and locally adjacent basins of different forest cover in Central Svitzerland was started in 1967. Precipitation and runoff in the basins were monitored for 4 to 13 years. Annual precipitation varied from 1700 to 2700 mm and runoff from 800 to 2300 mm. Evapotranspiration losses were highest in forested basins (600 to 600 mm) and more than twice as high as in basins with little forest cover. Flow frequencies are not clearly related to forest cover and seem to be more closely linked to soil and other characteristics of the basins. Nutrient input in precipitation as well as their loads in streamflow are given for each basin. The loadings for each nutrient are similar in most basins where extensive land use prevails. Intensive agricultural use seems to be related to increased loadings. The data available on water and nutrient budgets should be helpful to test models on runoff and nutrient discharge.