The rapid and intercontinental spread of avian influenza in 2005 and the potential for human pandemic influenza caused preparedness plans for such an event to be highlighted. The World Health Organization (WHO) has developed a global influenza preparedness plan, but this document does not address in detail the contribution necessary by the aviation community. The International Civil Aviation Organization, with assistance from WHO, the Airports Council International, and the International Air Transport Association, and others, has developed preparedness guidelines that are in accord with those of WHO but which are focused on the aviation aspects. Effective communication between stakeholders is the single most important issue that is addressed in the preparedness guidelines. States are recommended to appoint a clear contact point at the national aviation level that has responsibility for ensuring that all stakeholders are adequately consulted in the development of an aviation preparedness plan and that the relevant communication links are established. It is also important that the aviation preparedness plan is incorporated into the State's general preparedness plan, which demands efficient collaboration between the departments of health and transport at the government level. Communication with passengers, and those considering traveling, is important so that individuals are made aware of the risks associated with travel to particular parts of the globe and of the risk-reduction measures they may experience, or can take themselves, at airports and on aircraft. The guidelines will be web-based and will evolve as more knowledge becomes available.