Pasa la Voz (spread the word) is a human immunodeficiency virus (HIV) prevention methodology inspired by respondent-driven sampling (RDS) that uses social networks to access hard-to-reach populations. As field testing showed the approach to be efficacious among at-risk women in West Texas and Southern New Mexico, we set out to evaluate the methodology in a Mexican context. A local community organization, Programa Compañeros, first implemented a traditional one-on-one outreach strategy using promotoras (outreach workers) in Ciudad Juarez, Mexico, from September 2005 to January 2006. This was followed by implementation of Pasa la Voz from February 2006 to January 2007. The percentage of women agreeing to be tested increased from 11.9% to 49.9%, and staff time declined from 22.70 hours to 3.68 hours per HIV test, comparing the one-on-one with the Pasa la Voz methodology, respectively. Pasa la Voz was successful at imparting a cost-savings prevention education program with significant increases in the number of at-risk women being tested for HIV.