 Proven treatments exist that improve quality of life and reduce the risk of repeat heart attacks or death amongst persons who have already had one heart attack. These treatments include medications and supervised cardiac rehabilitation programs. Unfortunately, research shows that many people who have had a heart attack do not stick with these treatments and therefore cannot benefit. This quality improvement research program seeks to understand the impact of interventions that could be readily implemented at scale by entire health systems or organizations wishing to improve adherence to proven treatments. Specifically, the trial will test whether providing Ontario-based patients and their health professionals with repeated educational reminders delivered via post and phone will help improve the use of medications or attendance at cardiac rehabilitation. During the project, the types of patients who are most responsive will be identified as will the most cost-effective strategy for delivering reminders. The trial team are partnering in this project with health system decision makers who have an interest in using the results to create standard operating procedures that could benefit patients across the province. 