Acute aortic dissection (AD) is a life-threatening condition most frequently seen in men with an average age >60 years. Risk factors include family history, hypertension and cigarette smoking. AD has been associated with methamephatamine and cocaine use but has not previously been associated with the use of marijuana.We report a case of an aortic dissection in a 56-year-old male that occurred while smoking marijuana. The patient had a family history significant for both aortic aneurysm and dissection. He developed crushing chest pain, shortness of breath, and diaphoresis shortly after smoking marijuana from a glass pipe called a "bubbler". His ECG was unremarkable as was his chest x-ray and initial labs. CT scan revealed an Aortic dissection from the aortic root to the internal iliac artery. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The role of cannabis in cardiovascular disorders is complex and not completely understood. Acute chest pain associated with marijuana use typically raises concern for pneumothorax or pneumomediastinum. Marijuana has also been associated with hypertension and arrhythmias and has also been associated with an increased risk of myocardial infarction. However a link between marijuana and acute aortic dissection has not been previously reported. As more states legalize medical and recreational marijuana use this is a timely and important consideration for Emergency physicians evaluating chest pain. Our goal is to document the temporal relationship of cannabis use and acute aortic dissection in a recent ED patient.