A National Highway Traffic Safety Administration (NHTSA) rule requires electronic stability control (ESC) systems on trucks exceeding 26,000 lb. in gross weight, and is to be implemented in three phases beginning August 2017. Agency officials estimate it will prevent nearly 50 fatalities and more than 1,700 crashes and 600 injuries annually. They also credit ESC systems’ potential to curtail more than half of untripped, rollover crashes—those caused by striking an obstacle or leaving the road.