Six sigma is a way to measure the probability of manufacturing a product or creating a service with zero defects. Presents a case study to illustrate how the concept of zero defects, measured by six sigma, can be applied to customer satisfaction measurement and to examine the impact of customer expectations on the company’s strategies for improving satisfaction. The information presented is based on actual studies conducted for a high‐tech manufacturing company in the USA during 1991 and 1992. The performance and expectations values and some of the attributes have been altered for reasons of confidentiality.