Establishing standard operation procedure (SOP) is essential for every industry, especially for service industries. Since service is not easy to be judged objectively and is typically evaluated by users subjective opinions, it is better for any company to set up and then follow its own SOP to deal with daily activities. Moreover, another SOP should be established to meet the needs of incidents. With SOP, companies can promptly resolve any incident effectively and efficiently to show their willingness and abilities for their customers. Finally, several examples are illustrated to show the importance of SOP in different scenarios.