Thromboembolic disorders are common worldwide, frequently a leading cause of death. Judicial use of Anticoagulant plays an important role in the prevention and treatment of Venous and arterial thromboembolic diseases like deep vein thrombosis, pulmonary embolism, Stroke prevention in valvular and Non-valvular heart disease, and Acute coronary syndrome. Vitamin K antagonists, e.g., acenocoumerol and warfarin are commonly used as oral anticoagulants worldwide. The clinical use of oral anticoagulants has come a long way since their discovery over 50 years ago and Acenocoumarol is a coumarin derivative with pharmacological features closer to an ideal oral anticoagulant. Acenocoumarol is a drug with over 50 years of clinical experience and has been the subject of numerous clinical studies Acenocoumarol is prescribed once every day orally, as the anticoagulant is applied in various thromboembolic disorders. Amongst the coumarone, acenocoumarol is unique, with its rapid onset and offset of action and well documented efficacy and safety. Acenocoumarol has been shown to be superior to warfarin in maintaining INR stability within therapeutic range and efficacy. Despite the development of several new oral anticoagulants, coumarin anticoagulants remained unchallenged. Their efficacy has been established beyond doubt and they have long years of clinical experience. Forever 50 years since its discovery, acenocoumarol still continues to be widely used in India and various parts of the world.