Abstract Consideration of regional groundwater flow in aquifer systems allows for solving groundwater issues on a larger scale than single aquifers and contributes to all practical aspects of the UN’s Sustainable Development Goals for water. The approach has been extended to a wide range of hydrogeological environments. However, it suffers from poorly constrained terminology and conceptualisation, compounded by the difficulties of interpreting complex groundwater flow systems. This essay aims to initiate a discussion on improving the application of regional groundwater flow approaches.