The results of coronary event registration using the protocol of the World Health Organization MONICA Project are reported for two years for the Hunter Region, the area in and around Newcastle in New South Wales, Australia. The Newcastle MONICA Project monitors all suspected cases of heart attack by identifying patients from hospital admissions and obtaining information while they are still in hospital. For people who die out of hospital, the initial source of information is usually the death certificate. Rates for the most robust MONICA diagnostic categories, non-fatal definite myocardial infarction and all coronary deaths, differed for the two years reported here. Monthly rates suggested possible seasonal effects, and the possible influence of lower respiratory infections including an epidemic of influenza A. The results demonstrate that consistent monitoring over several years will be necessary to establish clear trends in coronary heart disease.