There are concerns that the rapid development of the developing countries will hasten global warming and exacerbate resource problems. That is to say, it is quite possible that we cannot solve the North-South problem while at the same time containing global warming and conserving fossil fuels. But this paper attempts to show that, on the contrary, the fast development of these countries might very well bring about a long-term solution of the global warming problem. A model incorporating development stage theory is built and used to calculate by region the world＇s economic growth, population growth, energy supply and demand, CO2 emissions and other items up to the end of the 21st century. Results indicated that if in 2100 world population is about 10 billion (it was 5.1 billion in 1990), world GDP is US$200 trillion (1987 prices; it was US$20 trillion in 1990) and CO2 emissions are 10 billion tonnes (carbon equivalent; they were 5.8 billion tonnes in 1990), there will be fairly good prospects for solving the North-South, fossil fuel exhaustion and global warming problems. Making this scenario happen will require accelerating development of the developing countries so they quickly join the ranks of the developed countries, expediting the shift to renewable energy in the developed countries by imposing carbon taxes, transferring energy saving technologies from the developed to the developing countries, and other efforts.