CVS customers will soon be able to get their prescriptions, along with other merchandise, delivered for free the next day—or even the same day in some cities. The move, announced Monday, will start in 2018, and USA Today reports it's likely a "preemptive strike" at Amazon, which is considering getting into sales of prescription drugs and has already obtained regulatory approval to become a wholesale pharmaceutical distributor in certain states. Same-day delivery will be available next year in Miami, Boston, Philadelphia, San Francisco, and the District of Columbia, Fortune reports; the service will start even earlier—Dec. 4—in Manhattan. Next-day delivery will be available at all the drugstore chain's other locations. (More CVS stories.)