This paper summarizes an assessment of future energy-technology strategies for China that explored the prospects for China to continue its social and economic development while ensuring national energy-supply security and promoting environmental sustainability over the next 50 years. The MARKAL energy-system modeling tool was used to build a model of China's energy system representing all sectors of the economy and including both energy conversion and end-use technologies. Different scenarios for the evolution of the energy system from 1995 to 2050 were explored, enabling insights to be gained into different energy development choices. The analysis indicates a business-as-usual strategy that relies on coal combustion technologies would not be able to meet all environmental and energy security goals. However, an advanced technology strategy emphasizing (1) coal gasification technologies co-producing electricity and clean liquid and gaseous energy carriers (polygeneration), with below-ground storage of some captured CO2; (2) expanded use of renewable energy sources (especially wind and modern biomass); and (3) end-use efficiency would enable China to continue social and economic development through at least the next 50 years while ensuring security of energy supply and improved local and global environmental quality. Surprisingly, even when significant limitations on carbon emissions were stipulated, the model calculated that an advanced energy technology strategy using our technology-cost assumptions would not incur a higher cumulative (1995-2050) total discounted energy system cost than the business-as-usual strategy. To realize such an advanced technology strategy, China will need policies and programs that encourage the development, demonstration and commercialization of advanced clean energy conversion technologies and that support aggressive end-use energy efficiency improvements.