Securing safe and reliable water and sanitation services for all is one of the leading challenges facing sustainable development. All but a few OECD countries have connected 100% of their populations to safe water supplies, and the majority are connected to wastewater treatment. Progress has also been made in developing countries, however, there there is still a long way to go before access is secured for all.

A key challenge is to ensure the financing necessary to extend water services to those that are currently not connected, and to maintain and to upgrade the existing infrastructure. Water is one of the three priority areas for the OECD.