A new campaign, known as "Six Sigma", to increase market share, decrease costs, and grow profit margins has been adopted by a selected group of leaders in American industry. Although the initial emphasis of Six Sigma was for quality improvement in manufacturing, it is rapidly being applied in key areas beyond manufacturing, and beyond what would traditionally be considered quality. There are a lot of Six Sigma success stories in companies such as Motorola, AlliedSignal, Asea Brown Boveri, and GE. The financial results of Six Sigma in those companies are investigated and their success factors are discussed. The applications of Six Sigma in Korean companies such as Samsung Display Device, Hanjung, and LG Electronics are also introduced.