young-looking photos, dozens had words to use as a selling point. >> most of the young people we work with who has been exploited on line talk about craigslist. they don't talk about the other sites. craigslist is like the walmart of on-line sex trafficking right now in this country. >> we post ads like around 4:00 or 5:00 and wait to get a call. >> from everything we understand, when they are being exploited by a pimp or a trafficer more accurately described, the trafficer is keeping the money. >> and if i didn't get it, he would beat me. >> so we're here at george washington university, and we just found out craig newmar, the founder of craigslist, is going to be speaking here. he doesn't know we're coming. he's very shy about all these allegations. it's his list. >> can people trust that children are not being sex