From 1991 to 1993, under the lead of National Science and Technology Commission and Ministry of Water Resources, the technical assistance project "Water Resources Management in North China" supported by UNDP. This project developed Macro-economics Based Water Resource Optimization and Allocation Model in North China, put focus on water supply and demand problem in water deficient cities such as Beijing, Tianjing, Taiyuan, Qindao and Huaifang and built respective water resource management model in these areas respectively. Besides, it also cultivated the backbone of China's water resources research, making a tightly coupled system between regional water resources research, regional macro-economy and decision science.