Communicable disease monitoring and response activities must be based upon local public health surveillance systems, even during infectious disease emergence, natural disasters, and during bioterrorism events. The NSW Department of Health has developed an emergency department surveillance system intended to monitor important public health conditions during mass gatherings and to identify outbreaks of importance. An evaluation of this system conducted in the Hunter New England region of New South Wales emphasised its usefulness when it was focused on a limited number of syndromes of public health importance and during mass gatherings and public health disaster responses.