Water features in almost all the 17 Sustainable Developments Goals (SDGs) in the UN’s new development agenda up to 2030. Embedding water in this way demonstrates its central role in all aspects of development and its importance to achieving the SDGs. This GWP Technical Committee Background Paper is a timely response this development and reviews the IWRM approach and its evolution over the past 25 years towards increasing water security – its successes and disappointments.