At one time U. S. Industry was the world leader in quality and productivity. However, in many markets, this situation no longer exists. American industry has systematically lost its competitive advantage to our offshore competition. In particular, the ability to engineer quality into basic product and process design, and then to translate this into a manufacturing system that operates at optimum effectiveness is a characteristic of our competitors. This paper discusses the role of experimental design methods in this activity, and provides examples illustrating the application of experiment design methods to process development and optimization.