Marathon and other road races are popular events in the United States with record participation that inspire people to pursue physical activity and are an opportunity for personal growth and accomplishment. However, the wide attention and large participation may make some events targets for terrorist attacks with the risk of mass casualties beyond the usual medical encounter level of the event. Race organizers should establish a chain of command modeled on the NIMS and the Incident Command System to improve event safety and help communities practice for mass casualty events. Organizers should address local risk factors, educate and allocate volunteers appropriately, and divide the course and medical resources in a well-organized manner with open communication lines. There are additional resources for those interested in race medicine and more information that can be obtained through local race organizations and the International Institute for Race Medicine (22).