Water management plays an important role in society since it intersects different technical, economic, technological, environmental and societal sectors and policy issues. For decades, sustainable management of water resources has been among the priority issues on the political agenda at different administrative (local, regional, national and interregional), hydrological (watershed, sub-catchment, catchment, river basin) and management (irrigation unit, district, consortia, industrial unit, municipality) levels and scales. The difficulties of properly approaching this topic are increasing since management solutions should be seen in the context of continuously altering spatial-temporal scenarios generated by climate variability and change, population growth and migration, land use transformation and socio-economic concerns. Therefore, the unceasing challenge is to embrace, in a comprehensive way, the numerous technical, socio-economic and environmental factors, institutional settings and stakeholders’ interests interplaying at all levels in the water management process.