In 2008, Cambodia passed a law that closed its brothels. The goal was to prevent human trafficking. But there was a tragic unintended consequence. It upended a government-run program designed to distribute condoms in brothels and screen sex workers for sexually transmitted diseases like HIV. But when the sex workers scattered, there was no easy way to reach them. Out of the shadows emerged a volunteer organization called SMARTgirl, comprised of active and former sex workers, that has been working to fill the void.