Abstract: Global hydropower capacity is projected to approximately double in the next several decades, powered by thousands of new dams. Most of this development will take place in South America, Africa, and Asia (China, South Asia, and Southeast Asia). While providing valuable energy to meet growing demands, this expansion of hydropower threatens the diversity and productivity of fish in many tropical rivers, including several river basins where fish provide the primary source of protein to rural communities and larger regional populations. Maintaining the movement of migratory fish within basins undergoing development is a key challenge for governments and those who plan, design, and manage dams. While improving fish passage at dams is critically important, this session will highlight how the spatial arrangement of dams in a river basin impacts fish movement through a channel network. The applied focus of the panel will be maintaining fish passage and migration within river basins that are undergoing development, with an emphasis on tropical rivers. The panel will review current examples of fish passage that illustrate the need for a basin-scale approach, tools for assessing connectivity of different dam configurations, and examine the potential for system-scale planning for dam siting to produced more balanced outcomes between hydroelectric energy and fish migration.