This work covers distributed hydrological modelling. The applicability of the distributed, physically-based approach for addressing environmental issues is dealt with in chapters on modelling of geochemical reactive transport, agricultural pollution and soil erosion. Through definition of a modelling protocol and methodology the book contributes to establishing more rigorous procedures for model setup, calibration, verification and validation. The challenges and future directions in hydrological modelling are addressed in a discussion between one of the principal critics and the editors. The target groups are hydrologists, engineers, water-asset managers and others working with hydrological modelling, either as researchers or practitioners.