Ecosystem services are defined as the provided and potential functions of an ecosystem which are effectively realized regarding human benefits (Maes et al., 2012). According to Target 2, Action 5 of the EU Biodiversity Strategy, member states are requested to map and assess ecosystem services (CBD 2010). In contrast to water quality monitoring, an ecosystem service assessment is not only referring to the state but the actual functions and processes within an ecosystem. The objective of this thesis is to perform an initial assessment of water-related ecosystem services in the Wupper catchment, (North Rhine Westphalia, Germany) which is highly modified by numerous dams. Therefore, the ecosystem service drinking water provision, habitat provision, water purification and tourism & recreation were assessed. The general level of drinking water provision and habitat provision is relatively low, whereas water purification shows slightly higher scores. The high scores of tourism & recreation are more concentrated on the Wupper than on the 21 tributaries. Also, the ecosystem services were investigated within a use profile. There, no direct correlations were found among the 52 management sections of the Wupper catchment. Furthermore, the water quality as assessed under the Water Framework Directive does not correlate with the ecosystem services. Lastly, ecosystem services are compared by stream characteristics, such as heavily modified and natural water bodies, river type as well as management sections with or without dams. While the modified of water bodies did not show significant correlations with ecosystem services, a correlation of drinking water provision and tourism & recreation in management sections with dams was found. Additionally, land use was taken into account. It was shown that, in management sections without dams, water purification correlates negatively with urban areas (R² = 0.36). When considering dams, several positive (synergies) and negative (trade-offs) correlations of ecosystem services and land use categories were found. Hence, this study provides the first explicit analysis of several ecosystem services for a multi-use river catchment in Germany.