People are becoming less inclined to trust information they get from their friends, a study by Edelman shows. The percentage of people who say they view their friends and peers as credible sources declined from 45% in 2009 to 25% in 2010, the study found. Edelman CEO Richard Edelman suggests marketers shouldn't rely solely on peer-to-peer marketing. "It's a more skeptical time," Edelman says. "If companies are looking at peer-to-peer marketing as another arrow in the quiver, that's good, but they need to understand it's not a single-source solution."