It's a first in the nation: New York City has allowed two safe drug injection sites to open as part of a harm reduction program aimed at tackling a surge of overdose-related deaths. At one of the two sites, in Harlem, drug users can find clean supplies and medical assistance in case of an overdose, see a doctor or take a shower. The executive director of OnPoint NYC, the non-profit that runs the sites, says they have prevented 134 overdoses. "The impacts we're having is less use of the emergency room," he says. But Dr Keith Humphreys, a Stanford professor working on drug prevention policies, thinks these sites won't do much to solve the opioid epidemic in the United States. "I have no doubt that they have very little effect on the epidemic as a whole," he says. IMAGES AND SOUNDBITES ARRANGED IN SEQUENCES