This guideline from the American Heart Association and American Stroke Association provides updated recommendations for the primary prevention of stroke. The guidelines were developed by a writing group comprised of experts from a variety of backgrounds and were reviewed by several organizations and content experts. The guideline covers general concepts such as the evaluation of evidence for stroke prevention and the importance of addressing social determinants of health, as well as specific recommendations for managing various risk factors including blood pressure, cholesterol, sleep, diabetes, tobacco use, and obesity. It also provides guidance on managing stroke risk in specific populations including those with sickle cell disease, genetic stroke syndromes, coagulation disorders, and pregnant women. The guideline further addresses the role of antiplatelet therapy in stroke prevention.