The Sydney 2000 Olympic Games (the XXVII Olympiad) will be the biggest peacetime event ever held in Australia. During the Games, all public health decisions will be centralised, with daily briefing sessions held to review emerging public health issues and facilitate responses. Infectious diseases will be monitored and reported through the Olympic Surveillance System, with particular attention to foodborne diseases and conditions spread via the respiratory route. This system relies heavily on the cooperation of key notifiers such as emergency departments, laboratories and general practitioners. The lessons learned during the Games, and the new and enhanced systems and linkages that have been developed to support it, will strengthen future disease surveillance in NSW.