The research presents at people's willingness to pay for the clean water supply in the city of Cao Lanh Dong Thap province

This paper is a study of the customer’s satisfaction to passenger service quality of the Tan Son Nhat international airport which based on the survey from 200 passengers at the domestic and international terminals. This study has been used the Key Performance Indicator to evaluate passenger service quality, and then build a linear programming for affected factors of customer’s satisfaction of passenger service quality at the Tan Son Nhat international airport. Important Performance Analysis model has been used in the paper to identify the most priority factors which should be improved for enhancing passenger service quality at the Tan Son Nhat international airport.