Using the critical incident technique, the authors collected 449 incidents from employees in banks, retails and restaurants. The incidents were categorized by utilizing Bitner,Booms and Mohr's classification scheme, and the results revealed that from an employee's perspective, the two major sources of customer satisfaction are the unprompted and unsolicited employee actions, employee response to customer needs and request. This is highly consistent with a previous study from a customer's viewpoint (Zhang Ping 2003). However, the findings that customer dissatisfaction mainly stems from employee's ineffective response to service delivery system failures, and from problematic customer behavior, are sharply in contrast with the results from the customer investigation