The paper summarizes the results of several cost analyses that were performed to evaluate the potential economic benefits of converting operating flue gas desulfurization (FGD) systems to organic-acid-enhanced limestone scrubbing systems. In addition, it summarizes the first 2 years of operation of the first full-scale system to convert to organic-acid-enhanced operation--City Utilities' Southwest Power Plant. Application of organic-acid buffer enhancement to FGD systems is a recent development that has resulted in lowered costs and improved performance for systems that have adopted its use. A process that uses organic acids as an additive has several advantages over conventional limestone scrubber systems, including: improved SO2 removal, decreased limestone consumption, increased system flexibility (e.g., ability to respond to unplanned fluctuations in coal sulfur content), and improved process reliability.