The future evaluation of surface waters shall cover the whole of Europe, it shall be ecological, type-specific, basin-based and comparable. The central aim is to achieve a “good status” for all European water bodies by the deadlines set. A good status is derived from a slight anthropogenic modification of the natural, as much as possible uninfluenced status and mainly defined along biological parameters in consideration of the specific water type. According to the WFD, surface waters have to be identified and characterised. The methodology for the characterisation is described in Annex II of the WFD. The present characterisation of Austrian running waters is based on purely abiotic factors and is the first substantial basis for the implementation of the ecological characterisation in accordance with the WFD. In how far these abiotic water types are reflected in the water biocenosis is going to be analysed in the next working step. This study including the relevant database with the abiotic characterisation of the Austrian running waters (with a catchment larger than ten square kilometres was compiled for the Federal Ministry of Agriculture, Forestry, Environment and Water Management is available from Amedia, Sturzgasse 1a, A–1141 Vienna, Tel. +43 1 982 13 22-310 or 365, Fax +43 1 982 13 22-311.