There is a good level of understanding of the local hydrological effects of most NFM measures. However, the wider hydrological impacts of NFM measures at the catchment scale are less clear. This topic includes research on the effects of NFM, as well as research that supports delivery, such as social research on land managers attitudes to NFM or barriers to implementation. Scientific research is available in all forms and scales, for example, from empirical studies to new modelling tools and from the plot scale to the full catchment scale.