A discussion of the commercialization of advanced technology to control emissions from the combustion of coal for the production of electricity is presented. A historical summary of the development of flue gas treatment technology, some approaches to process development, the factors affecting the success of new flue gas treatment concepts, and a general strategy that may be applied to the development of these new concepts are provided. The scrubbing of utility flue gas is a relatively new practice. Even though the first application of flue gas scrubbing for sulfur dioxide control occurred in London, England, in 1933, the application of this technology to coal-fired utility boilers in the United States did not begin until the 1970's. The difficulty in controlling emissions from coal-fired utility boilers lies in the tremendous volume of flue gas to be treated. The scale is so large, and the capital and operating expenses are so great that utility companies enter into flue gas treatment with great caution. Most newly conceived flue gas treatment systems do not advance beyond laboratory or small-scale pilot testing.Factors affecting the success of these new concepts are capital equipment costs, operating costs, system reliability and performance, and waste disposal requirements. The acceptance of a novel flue gas treatment technology requires that confidence in system reliability be built through intense, large-scale testing.