A control/intervention study carried out in Santiago, Chile assessed the impact of five interventions on breastfeeding patterns and duration, and demonstrated a significant increase in full breastfeeding at six months (32 percent to 67 percent). Fifty-nine of 422 post-intervention women were included in a sixth intervention: prenatal group educational sessions emphasizing the skills necessary to initiate and maintain breastfeeding past the neonatal period. A significantly higher percentage of this subset of women were fully breastfeeding at six months compared to those who received only the five basic interventions (80 percent and 65 percent, respectively). The effect was greater among primiparous women. We conclude that prenatal group education with hands-on skills reinforcement is a significant and additive component of breastfeeding support, especially among those who have no previous breastfeeding experience.