Polycarbonate (hereinafter referred to as "PC ") is the sole product having good transparency among the 5 major engineering plastics. In 2000, the worldwide PC production capacity was reached up to 2,800,000 tons of several hundreds of brands of various grades. It is estimated that the global PC production capacity will exceed 3,500,000 tons in 2005. The global demand for PC was 1,900,000 tons in 2000, which will reach to 2,600,000 tons and more than 3,000,000 tons in 2003 and 2005 respectively according to relevant estimations. The total production capacity of PC of the whole country reached to 3000-4000 tons in 2003. PC imported to China in 2003 was up to 534,000 tons and the apparent amount of consumption of that year was 447,000 tons.The scientific and technical personnel of Chenguang Chemical Research Institute engaged in the research and development of PC production technologies have been advancing wave upon wave with a combatant spirit and the spirit of "Storming the gate" for more than 40 years, having made important breakthroughs in a continuous PC manufacturing process by using ester-interchange method and in project amplification techniques. We consider that favorable conditions are now already available in China for building up PC production plants (each has an annual production capacity of 10,000 tons or above) by using ester- interchange method.In the recent 2 years, the growth rate of domestic annual PC consumption was up to more than 30 %, almost all of which relied on imports from foreign countries. Consequently, the development of domestically made PC has become a task, which brooks no delay. At present, conditions for building up domestic large-scale PC production plants are already available. It should be noted that PC production technologies are matured, PC products have a huge market potential and the returns on investment are optimistic. Therefore, building PC production plants, each with an annual production capacity of 10,000 tons ( approx. ) making use of domestic scientific research achievements and engineering technologies are fully in conformity with the industry policies issued by the State, which will have very important practical significance and far-reaching strategic significance for alleviating a sharp contradiction between PC supply and demand existed in China nowadays, breaking down the blockage against PC production technologies in China and the monopolization over the supply of PC products and product prices of foreign companies and developing our national industries having our own autonomous intellectual properties by means of our own intellectual properties.