Those on the front lines of the fight against predators on the Web, who use social-networking sites to find young people and lure them to meet, say the battle is complex and will take a combination of education, high-tech security, old-fashioned investigative work, and cooperation among police, lawmakers, schools, parents, teens and the sites. "This isn't going to be something that we just solve," said Chad Harms, an assistant professor at Iowa State University who serves on the advisory council for the Iowa Internet Crimes Against Children Task Force.