In many countries of the World Health Organization (WHO) South-East Asia Region, drinking water is not used directly from the tap and faecal contamination of water sources is prevalent. As reflected in Sustainable Development Goal 6, access to safer drinking water is one of the most successful ways of preventing disease. The WHO Water Safety Framework promotes the use of water safety plans (WSPs), which are structured tools that help identify and mitigate potential risks throughout a water-supply system, from the water source to the point of use. WSPs not only help prevent outbreaks of acute and chronic waterborne diseases but also improve water-supply management and performance. During the past 12 years, through the direct and indirect work of a water quality partnership supported by the Australian Government, more than 5000 urban and rural WSPs have been implemented in the region. An impact assessment based on pre- and post-WSP surveys suggests that WSPs have improved system operations and management, infrastructure and performance; leveraged donor funds; increased stakeholder communication and collaboration; increased testing of water quality; and increased monitoring of consumer satisfaction. These achievements, and their sustainability, are being achieved through national legislation and regulatory frameworks for water supply, including quality standards for drinking water; national training tools and extensive training of sector professionals and creation of WSP experts; model WSPs; WSP auditing systems; and the institution of longterm training and support. More than a decade of water safety planning using the WSP approach has shown that supplying safe drinking water at the tap throughout the WHO South-East Asia Region is a realistic goal.