SDG indicator 6.5.2 measures cooperation on both transboundary river and lake basins, and transboundary aquifers. In this second report on SDG indicator 6.5.2, you can learn more about the progress of transboundary water cooperation. This second SDG indicator 6.5.2 report seeks to build upon both the findings and recommendations set out in the first report published in 2018. It presents the advances made since the initial exercise, including the increased number of countries that engaged in the exercise and improvements in the quality of data submitted. The report also provides a synthesis analysis of country data at both the global and regional levels across both 2017 and 2020 monitoring exercises. Finally, this second report reflects upon the recommendations made in the first report, and considers the further actions needed to accelerate progress on transboundary water cooperation, particularly in light of the SDG 6 Global Acceleration Framework and the United Nations Decade of Action.