Objective: To assess the short-term effects of an obesity prevention program promoting eating self-regulation and healthy food preferences in low-income Hispanic children. Design: Randomized controlled trial with pretest, posttest, and 6- and 12-month assessments. Setting and Participants: Head Start and similar early learning institutions in Houston, TX, and Pasco, WA. A total of 255 families with preschoolers randomized into prevention (n = 136) and control (n = 119) groups. Intervention: Multicomponent family-based prevention program. Fourteen waves lasted 7 weeks each with 8-10 mother-child dyads in each group. Main Outcome Measures: Parent assessments included feeding practices, styles, and knowledge. Child assessments included child eating self-regulation, willingness to try new foods, and parent report of child fruit and vegetable preferences. Parent and child heights and weights were measured. Analysis: Multilevel analyses were employed to consider the nested nature of the data: time points within families within waves. Results: The program had predicted effects on parental feeding practices, styles, and knowledge in the pre- to post-comparisons. Effects on child eating behavior were minimal; only the number of different vegetables tried showed significant pre-post differences. Conclusions and Implications: Short-term effects of this prevention program highlight the importance of family-focused feeding approaches to combating child overweight and obesity. (author abstract)