Integrated operation of hydropower stations and reservoirs has become a trend of hydropower exploitation, as an effective technical measure, integrated operation can improve the utilization efficiency of water resources, reduce the risks of flood and drought disaster, increase the safety and stability power grid and make sure that hydropower stations and reservoirs operate in an appropriate and economical way. This bulletin gives an overview of the main functional and operational aspects relating to cascade hydropower stations and reservoirs, it was formed by reviewing of all the related aspects proposed and case studies provided by committee members. It collected and sorted out operation modes and practical experiences of hydropower stations and reservoirs in ICOLD member countries, summarized the feasibility measures, benefit evaluation methods and system platform construction of hydropower stations and reservoirs with comprehensive benefits, and shared case studies from 10 countries, including Brazil, China, France, Iran, Japan, Korea, Nigeria, Russia, Switzerland and USA.