The news that Hong Kong is moving to set up a Centre for Health Protection should be welcomed. Now that the commitment is there, the success of such a centre will depend on how the details are carried out. Here, the government has a head start in the form of recommendations from the Sars expert committee, which delivered its assessment of the outbreak several months ago. The committee not only recommended the establishment of the centre, but also spelled out what the main priorities should be and how it should relate to existing health agencies. The government has taken up the committee's suggestion that the centre be an adjunct to the Department of Health, which played a large role in co-ordinating the response to Sars this spring. It will be headed by the director for health and a controller nominated from the department. One would set the overall direction, while the other would execute day-to-day planning and administration. This structure, and the plan to make outbreak response and epidemiology the first priorities, is appropriate. One vital issue raised by the experts that has yet to be addressed is the need to establish the primacy of the centre and the Department of Health in any outbreak situation. The report noted that these agencies should have the authority to take the lead in investigating and responding to emergencies, on public and private premises. It also called for legal recognition of this role. Government officials, in making their announcement, hinted that this could be forthcoming by referring to a continuing review of laws on communicable diseases. The sooner this is done, the better. For it was the lack of clarity over this issue that led to some of the confusion surrounding our response to Sars this spring. The committee noted that the department was involved in investigation, data analysis and contact tracing. But it also highlighted the fact that the department was not called upon early on in the outbreak at the Prince of Wales Hospital. Instead, officials read about it in the newspaper and had to ask if it could become involved in the hospital's outbreak response meetings. Without clarity on the chain of command in just this type of scenario, we risk a repeat of the confusion that entered the picture this year - and a waste of the resources about to be poured into the centre. Two branches to be set up by the middle of next year include the surveillance and epidemiology branch and the infection control branch. It is encouraging to see that cross-border monitoring is on the agenda for the former. At last, there will be a more formalised mechanism for liaising with the mainland's health agencies on a topic of prime concern to residents on both sides of the border. The expert committee also recommended expansion of the list of notifiable diseases. Sars and the Japanese encephalitis cases this autumn showed that review of this list is essential. The list has to be manageable, but the criteria and mechanisms have to take into account that we live in a hot spot for emerging infectious disease. One other public health concern highlighted by the Sars expert committee was that Hong Kong lacked an appropriate level of expertise with regard to epidemiology and communicable disease. The centre can help address this by creating new staff positions for these specialists, as well as training programmes for personnel throughout the health-care system. Establishment of the centre should address some of the most significant systemic deficiencies exposed by the Sars outbreak. There is no clear picture of the funding required. But considering the risk Hong Kong and the region faces from infectious disease, the centre should be adequately funded and given the authority necessary to accomplish its task.