Drug overdoses now kill more Americans annually than guns, cars, or breast cancer. But the United States has tried to solve this national crisis with policies that only made matters worse. In the name of “sending the right message,” we have maximized the spread of infectious disease, torn families apart, incarcerated millions of mostly Black and Brown people—and utterly failed to either prevent addiction or make effective treatment for it widely available. There is another way—one that is proven to work. However it runs counter to much of the received wisdom about substances and related problems. It is called harm reduction. Created by a group of people who use drugs and by radical public health experts, harm reduction offers a new way of thinking—one that provides startling insights into behavioral and cultural issues that go far beyond drugs.