Modelling the catchment hydrologic response is hampered by many factors. Due to large uncertainties of input data, structural complexity, model parameterization and validation data, frequently the prediction of catchment behaviour is not a straightforward task. Therefore, the use of rainfall-runoff models into small catchments, where detailed data are available, may not only contribute to a better understanding of the rainfall-runoff processes, but also allows to assess the reliability of the models themselves. In this study, a continuous rainfall-runoff model, based on an intense hydro-meteorological monitoring activity in research watersheds, was applied to three European experimental catchments characterized by different climatic and physiographic conditions. Results show that the model can be considered as a useful tool to investigate runoff dynamics within these catchments and highlight the importance of the soil moisture-runoff threshold relationship in characterizing the catchment hydrological behaviour.