The time that elapses from the onset of symptoms of acute myocardial infarction (AMI) to treatment has a significant effect on mortality and morbidity. This study reports the effectiveness of an education and counselling intervention on knowledge, attitudes and beliefs about AMI symptoms and the appropriate response to symptoms. The intervention was tested in a randomised controlled trial of 200 people with a history of coronary heart disease (CHD). The groups were equivalent at baseline on study outcomes, clinical history and sociodemographic characteristics with the exception of more women in the intervention group (38% vs. 24%). The results of repeated measures ANOVA showed that the intervention resulted in improved knowledge of CHD, AMI symptoms and the appropriate response to symptoms that was sustained to 12 months (p=0.02). There were no differences between groups' attitudes and beliefs over time. It is concluded that a short individual teaching and counselling intervention resulted in improved knowledge of CHD, AMI symptoms and the appropriate response to symptoms in people at risk of AMI sustained to 12 months.