Ischemic strokes account for 87% of acute strokes, and 12% of patients with acute ischemic stroke have recurrence within 5 years. After an acute ischemic stroke is identified, several tools can be used to help detect the likely cause. Controlling cardiovascular risk factors with antihypertensive therapy (with a goal of 130/80 mm Hg), statin therapy, blood glucose control, healthy diet, regular exercise, avoidance of substance use, treatment of obstructive sleep apnea, if present, and care based on the cause of stroke reduces the risk of recurrence. Antithrombotic therapy with anticoagulants is recommended for embolic stroke due to atrial fibrillation; antiplatelet therapy is more commonly used for the treatment of nonembolic stroke. Procedural management for those with carotid stenosis or closure of patent foramen ovale may be indicated. Additional evaluation, such as long-term cardiac monitoring to identify initially undetected atrial fibrillation, may be required if the cause of stroke is unclear.