This article reviews the history and progress of the computerisation of accident and emergency departments in Hong Kong. The Hospital Information System was the first computerisation project to be launched in a public hospital in Hong Kong, when the Princess Margaret Hospital was selected as a pilot site in April 1991. The network infrastructure comprised a central processor that linked to all workstations in the hospital in an integrated network. With the introduction of bar-coding technology and the implementation of an interfaced network, the Accident and Emergency Information System version 1.0 was launched at the Prince of Wales Hospital in March 1993. A Clinical Management System was then piloted at the Accident and Emergency Department of the Alice Ho Miu Ling Nethersole Hospital in December 1997; it contained clinical data of individual patients, including diagnoses, drug treatments, discharge summaries, allergies, and medical histories. Laboratory, diagnostic radiology, and electrocardiography results were also available in this system. With the extensive development of Internet technology within the Hospital Authority, clinical information can now be retrieved in any hospital in a couple of minutes. The availability of important clinical information will be of great help to emergency physicians in the delivery of quality care to patients.