Coronary artery diseases (CADs) are preventable and controllable disorders, but they continue to be a major cause of morbidity and premature mortality across globe. India is projected to have 62 million CAD patients by 2015, with nearly 1/3rd of this burden shared by patients younger than 40 years. The renin-angiotensin-aldosterone system (RAAS) plays a pivotal role in blood pressure (BP) regulation and fluid and electrolyte homoeostasis. Activation of RAAS has long been implicated in the pathogenesis of acute myocardial infarction (AMI) and benefits of inhibition of RAAS as an effective way to intervene in the pathogenesis of AMI is well documented. In the setting of AMI, angiotensin-II plays a significant detrimental role, contributing to cardiac remodeling, a process that predisposes to subsequent arrhythmia and cardiac failure. Angiotensin converting enzyme inhibitors (ACEls) play a key role in the clinical management of several cardiovascular disease (CVD)s such as AMI, by inhibiting the actions of angiotensin-II, ACEIs would be expected to modify unwanted post-AMI events. ACEIs trials have tested AMI patients with two different approaches: selective (those with left ventricular dysfunction (LVD) treated over a long-term) and relatively unselective (those treated early over the course and for a short-period, up to 6 weeks). In general, results are consistent and beneficial as regards to reduction in both short-term & long-term mortality and heart failure. There are evidences that suggest yielding of an extra protection (reduced mortality and occurrence of severe LVD) with early introduction of ACEIs in the course of AMI. Trials have also shown ACEIs effective and consistent protection against re-infarction and management of arrhythmias after AMI. Large clinical trials have proven ACEIs to be superior to ARB, in preventing CV deaths in high-risk AMI subjects. They have proven to be safe & effective in diabetic & older population. With wealth of evidence available supporting use of ACEIs in patients with MI, The use of ACEIs in AMI has moved form experimental to standard therapy.