UNESCO published a report on transboundary water cooperation and the Sustainable Development Goals (SDGs). The UNESCO International Hydrological Programme (IHP) in partnership with the Strathclyde Centre for Environmental Law and Governance (SCELG) prepared the report in the context of the ongoing negotiations on Target 6.5 indicators calling countries to implement integrated water resources management (IWRM) at all levels. The Sustainable Development Goals are in a crucial phase. After their adoption in September 2015, countries are now engaged in devising the indicators that will measure the success of the SDGs. Target 6.5 calls countries to implement IWRM at all levels, including through transboundary cooperation as appropriate by 2030. A first set of indicators for Target 6.5 only focused on IWRM without a much needed attention on transboundary water cooperation. IHP and SCELG, produced the report on transboundary water cooperation and the SDGs in the context of the ongoing negotiations on Target 6.5 indicators. The report makes a case for a second indicator for Target 6.5 that refers to transboundary water cooperation.