This report contributes to a broader body of OECD work on water, biodiversity and climate, with a particular focus on financing models that generate lasting outcomes.
The report was developed in the context of the Roundtable on Financing Water, a joint initiative of the OECD, the World Water Council, the Netherlands and the World Bank. The Roundtable draws upon political leadership and technical expertise, with the ambition of facilitating increased financing of investments that contribute to water security and long-term growth. More specifically, the research work conducted in preparation for the 12th meeting of the Roundtable on Financing Water led to this publication. This Roundtable meeting took place at the Islamic Development Bank’s headquarters in Jeddah, Saudi Arabia, in April 2025, and gathered 400 leaders and experts on finance and water.
Water-related investments are instrumental in advancing development, not only by enhancing water security but also by supporting other economic sectors, including agriculture, industry, energy, health and education. Yet, the long-term viability of some water-related investments remains an area of concern across both OECD and non-OECD countries.
The report aims to explore funding and financing models that can strengthen the long-term viability of water-related investments or mobilise capital at scale for durable investments in water. It focuses on bond finance, public–private partnerships, results-based finance, and Islamic finance instruments - each offering the potential either to mobilise under-used pools of capital seeking impact-driven investment opportunities or to support the design of financial instruments aligned with lasting outcomes.