This report distils key messages from the Roundtable on Financing Water, a joint initiative of the OECD, the Government of the Netherlands, the World Water Council and the World Bank, and related analytical work on financing water. The report benefitted from the engagement of several hundred participants in Roundtable meetings organised over the past five years, including global, regional (the Americas, Asia, Europe) and thematic meetings (on agricultural water and on climate action). Through partnerships with member countries (Israel, the Netherlands and the United States), key regional players (Inter-American Development Bank, Asian Development Bank, European Investment Bank) and other key organisations (the United Nations Food and Agriculture Organization), the Roundtable’s meetings have allowed for a deeper exploration of the contextual factors that influence financing approaches in different regions and investment types. This provides the basis for an up-to-date summary of the key challenges and opportunities in the water financing landscape and sets out a vision for future OECD work on financing for water security and the Roundtable.