This article illustrates a Web-based health information system that is comprised of specific information exchange standards related to health information for healthcare services in National Taiwan University Health System. Through multidisciplinary teamwork, medical and informatics experts collaborated and studied on system scope definition, standard selection challenges, system implementation barriers, system management outcomes, and further expandability of other systems. After user requirement analysis and prototyping, from 2005 to 2008, an online clinical decision support system with multiple functions of reminding and information push was implemented. It was to replace its original legacy systems and serve among the main hospital and three branches of 180-200 clinics and 7,500-8,000 patient visits per day. To evaluate the effectiveness of this system, user surveys were performed, which revealed that the average score of user satisfaction increased from 2.80 to 3.18 on a 4-point scale. Among the items, especially e-learning for training service, courtesy communications for system requests, and courtesy communications for system operations showed statistically significant improvement. From this study, the authors concluded that standardized information exchange technologies can be used to create a brand new enterprise value and steadily obtain more competitive advantages for a prestige healthcare system.