In the past decades, there has been a significant development in the management of patients with acute coronary syndromes (ACS), largely driven by advances in antithrombotic and antiplatelet agents. Despite significant improvements in efficacy end points such as death, myocardial infarction and repeated revascularization, these therapies are still associated with a significant risk of bleeding. Such bleedings are independent predictors of long-term adverse clinical events. Data that are currently available on the magnitude and the predictors of bleeding complications in patients with ACS have been obtained from randomized clinical trials. However, patients perceived to be at higher risk of complications, including the elderly or those with renal insufficiency, are often excluded from these trials, but constitute a significant percentage of patients treated for ACS. For these reasons, new bleeding risk scores are under evaluation to facilitate management and subsequent treatment decisions in the real world. Better identification of higher risk patients, careful dosing and appropriate monitoring of antithrombotic therapies, and incorporation of various peri-procedural strategies in routine clinical practice may potentially reduce the risk of bleeding of patients with ACS and further improve their clinical outcomes.