Target 6.5 is: “By 2030, implement integrated water resources management at all levels, including through transboundary cooperation as appropriate.” Indicator 6.5.2 looks at the area of a country within transboundary basins and assesses the extent to which that area is covered by operational cooperation arrangements. Transboundary basins are river, lake and aquifer systems shared between two or more countries. Arrangements are “operational” when there is a joint body, meetings between countries take place and information is exchanged at least once per year, and joint or coordinated management plans or objectives for the basin(s) have been set. Transboundary waters account for 60 per cent of the world’s freshwater flows and 153 countries have territory within at least one of the 286 transboundary river and lake basins and 592 transboundary aquifer systems. This report presents the global status on transboundary cooperation and acceleration needs to achieve target 6.5 by 2030, based on the latest data on indicator 6.5.2.