All of these aim to balance a more technocratic, built-infrastructure approach that has tended to dominate water resources management, by recognizing the contribution that ecosystems can make. Ecohydrology is an integrative science that focuses on the interaction between hydrology and biota (Box 1.1). Ecosystem-based management and ecosystem-based adaptation or mitigation involve the conservation, sustainable management and restoration of ecosystems. Environmental flows describe the quantities, quality and patterns of water flows required to sustain freshwater and estuarine ecosystems and the ecosystem services they provide.