Water management is a pressing 21st century problem because human demand for reliable water supplies and environmental quality keep rising. As London’s ‘Global University’, water researchers at UCL work on a host of international water challenges. These include water security strategies, emerging water contaminants removal, sustainable solutions for access to safe and affordable water, sanitation and hygiene (WASH), adaptation of water and sanitation systems to climate change impacts, innovative materials for water systems etc. Water management in England and in London’s Thames basin also leads to fascinating research problems. A high population density combined with relatively low rainfall in South East England leads to excessive water demand during droughts. Local water management approaches include water desalination, water reuse strategies, innovative water demand management programs, water markets etc. Flooding, water quality and ecological habitat protection present further problems. Recovery and restoration of urban aquatic ecosystems through technical solutions and community participation are a challenge we are addressing through research projects and partnerships. Over a dozen PhD students and a large group of MSc students make for a stimulating and productive environment. Expertise from UCL’s other world class researchers in planning, spatial analysis & GIS, hydraulics, hydrology, hydrogeology, statistics, geography, economics, computer science, chemistry, chemical engineering, operations research, etc. ensure high quality interdisciplinary interactions.