Objective: Formula-fed infants gain weight faster than breastfed infants. This study evaluated whether encouraging formula-feeding caregivers to be sensitive to infant satiety cues would alter feeding practices and reduce infant formula intake and weight gain. Design: Double-blind, randomized educational intervention, with intake and growth measured before (at 1 to 2 months) and after (4 to 5 months) the intervention. Setting: Women, Infants, and Children (WIC) clinics in Sacramento, California. Participants: 836 caregivers of young infants were screened; 214 were eligible, and 104 agreed to participate. Intervention: Intervention subjects received education promoting awareness of satiety cues and discouraging bottles containing more than 6 ounces before 4 months of age; intervention and control groups received education regarding introduction and feeding of solid food after 4 months of age. Main Outcome Measures: Formula intake (mL/24 hours) and weight gain (g/week). Analysis: Differences between groups evaluated using 2-way analysis of covariance (ANCOVA). Results: Sixty-one subjects completed baseline records, 44 attended class, and 38 completed the study. Despite a positive response to the educational intervention, there was no change in bottle-feeding behaviors (formula intake at 4 to 5 months was more than 1100 mL/day in both groups). Infant growth in the intervention group was greater than in the control group (P less than 0.01), contrary to the hypothesis. Conclusions and Implications: The intervention improved knowledge of the key messages, but further research is needed to understand barriers to modifying bottle-feeding behaviors. (Contains 1 table.)