Two outreach interventions conducted with young drug users in Santiago, Chile are presented: a systemic family outreach intervention (SFOI) and another based on the usual outreach work (OW). The key elements involved in the successful performance of 8 community agents are discussed, as revealed by a qualitative analysis of the records of the selection, training, and ongoing supervision processes that they received. Agents recruited 138 drug users, achieving a retention rate of 93% at 6 months of intervention and 81% after a year of follow up. The working alliance established between young people and community workers was assessed in 3 phases of the intervention through the Horvath questionnaire, comparing both types of intervention by Mixed ANOVA of Repeated Measures. The results indicate that while in SFOI the alliance was sustained over time, in OW it decreased; however, it is possible to develop a quality outreach work with community agents who are professionalized and paid. An agents' successful profile includes being a young adult, with territorial and cultural proximity to the target population, community motivation, and good relational skills with young people.© 2013 by Psykhe.