Cities in OECD countries have not solved water management. While they currently enjoy relatively high levels of protection against water risks, they face disquieting challenges, including the proven difficulty of upgrading and renewing existing infrastructures, and heightened uncertainty about future water availability and quality. Cities in OECD countries are entering a new era, characterised by the need to retrofit existing assets into more adaptable infrastructure, by different combinations of financing tools and by new roles for stakeholders in water management. The transition to this new era requires co-ordinated action among central governments, local authorities and a variety of private actors.