This paper considers U.S. management philosophy in the auto industry as it impacts on the strategy for improving quality control practices. We find that existing practices often have consequences contrary to intended goals. These practices are contrasted to those operative in the Japanese auto industry. General background factors influencing the Japanese approach as well as a specific description of quality control practices in the Japanese auto industry are introduced. We describe the Quality Control Circles operative in Japanese auto firms. The ways in which these circles contribute to the mobilization of worker potential is described. The original research described here was conducted at Toyota Auto Body.