Since 1983, United has maintained a continuous tracking survey for measuring customer satisfaction. In 1990, United began serving European markets and this program was extended to our European flights. This paper describes how United uses this consumer data to ensure quality service in Europe. Methodology for the survey program will be described in detail. Case histories will be presented demonstrating four uses of the data in maintaining Uniteds service level: monthly reviews of trends in customer service ratings, ad hoc analyses, service concept testing, and ongoing custom analysis. With United's ongoing tracking system United can test new concepts, monitor trends in service, and analyze the success of any product changes. This system allows United to monitor and improve our service to the customer which should ultimately lead to increased market share and higher profits.