When Billy Lemon was trying to kick his methamphetamine addiction, he went to a drug treatment program at the San Francisco AIDS Foundation three times a week and peed in a cup. If it tested negative for meth, he got paid about $7.

“For somebody who had not had any legitimate money – without committing felonies – that seemed like a cool thing,” says Lemon, who was arrested three times for selling meth before starting recovery.

The payments were part of a formal addiction treatment called contingency management, which incentivizes drug users with money or gift cards to stay off drugs. At the end of 12 weeks, after all his drug tests came back negative for meth, Lemon received $330. But for him, it was about more than just the money. It was being told, good job.

“It was the first opportunity where I was like, I have self-worth, still. It’s buried. This person sees it and is willing to give me seven dollars, just to take care of myself. That was very motivating,” he says.