With 90 percent of the water in Africa falling within 63 river basin catchments crossed by multiple borders, water resources management and development must be a cooperative endeavor. The Cooperation on International Waters in Africa (CIWA) Trust Fund works to strengthen institutions, improve knowledge, develop investment opportunities, and train governments to cooperate across shared waters. The presentation will draw upon CIWA engagement and experiences in addressing transboundary water management and also include global examples. In order to address the current climate and development challenges action on transboundary water is imperative. Without concrete climate action and climate-sensitive development, as many as 86 million people in Sub-Saharan Africa could be forced to relocate by 2050 from water scarcity, sea level rise and storm surges, and declines in crop and ecosystem productivity. Tapping into Africa’s water resources can significantly strengthen the region’s water security, improve livelihoods, and spur economic growth. Improved water resources management can increase food security, reduce vulnerability to climate change, improve human health and sanitation, and increase energy generation and industrial expansion.