The purpose of this study was to investigate the operation of the Hoabinh reservoir in the Red River Basin of Vietnam, and assess the room for its improvement by application of system analysis and optimal control techniques. The study aimed at establishing a foundation for further research on inter-reservoir regulation of the Basin. Finally, this study provided a testing ground for developing and comparing di erent reservoir optimization methods. Chapter 1 and 2 provide a general and mathematical description of the socio-economic and physical system of the Red River Basin, including the three main objectives of hydropower production, ood control, and water supply.