The objective of this study was to assess the current level of computerization in clinical practice in Hong Kong through a population-based, physician survey conducted in 2000.A self-completed, 20-question, postal questionnaire was sent to 4850 randomly selected doctors in Hong Kong. We received 897 completed responses. Over one-third of doctors in the overall sample were already recording patient summaries, processing laboratory results and specialist reports, and preparing referral notes electronically. Patient registration (52.2%), billing systems (40.2%), appointment scheduling (39.9%), and payroll (36.9%), were the commonest administrative functions to have been computerized. Seventy per cent of doctors in solo or small-group ('individual') practices did not yet have any clinical function computerized compared with only 30.7% for those working in large, corporate organizations. Similarly, approximately two-thirds of administrative tasks in 'individual' clinics were not computerized, while corporate physicians reported a corresponding percentage of 39.3%. Younger age, male gender, specialist qualifications, more computers in the practice, higher numbers of administrative tasks already computerized, higher levels of knowledge about and positive attitudes towards computer applications in clinical practice were all positively associated with more clinical tasks already computerized in the practice. The present study has systematically documented the extent of clinical computer use in Hong Kong and identified areas for improvement as well as specific groups of physicians who might benefit from targeted efforts promoting computerization in practice.