Abstract: A Hospital Information System (HIS) is designed to manage the information needed by health professionals to perform their jobs effectively and efficiently. Hospital Information Systems that are totally integrated and able to satisfy the information processing requirements of various functional blocks of a hospital are still in infancy. As the progress in ICT (Information and Communications Technology) continues at an ever-increasing pace, new applications of ICT are emerging in the domain of a HIS. These new applications have resulted in a massive data overload for a typical HIS of today. Work is therefore continueing to cope with the requirement in increased throughput and data processing. However these advancements concentrate on improving the existing structure of HIS. A HIS based on the already proven concept of Autonomous Decentralized System is proposed in this study. The proposed structure exhibits the potential to handle the performance requirements of future Information Systems in a Hospital setting in addition to the typical advantages of ADS namely the on-line maintenance, fault tolerance and on-line expansion. A software subsystem installed in each of the distributed computers has an autonomous function for self-management and is capable of coordinating with other subsystems. Each subsystem decides to accept data based on the content code of the message. The ADS concept has already been applied to a number of Information Processing/Control Applications successfully.