Arterial ischemic stroke (AIS) in a child can have devastating, lifelong sequelae. Given the infrequency of AIS (approximately 3 per 100 000 children), primary prevention is probably not feasible in the absence of a known risk factor. However, the prevention of recurrent AIS in childhood, ie, secondary prevention, may be feasible. How can recurrent childhood AIS be prevented? Current consensus guidelines on the use of antiplatelet and anticoagulant therapy for AIS in children are not based on randomized controlled trials (RCTs).Detailed knowledge of the rates and predictors of AIS recurrence in children is essential before appropriate RCTs can be designed and before rational treatment guidelines can be promulgated. The article by Ganesan et al in this issue of Circulation provides new information in this regard.