Objective: To examine the association between child care practices and child care provider knowledge and beliefs about their role in supporting children's healthful eating. Design: Longitudinal design using survey and observation data from baseline and year 1 of the Encouraging Healthy Activity and Eating in Childcare Environments (ENHANCE) pilot project. Participants: Seventy-two child care providers from 45 child care settings. Main Outcome Measures: Child care setting variables included the feeding environment, nutrition education, and family communication. Child care provider variables were efficacy, knowledge, and misconceptions about child feeding; and the priority placed on supporting children's healthful eating. Data Analysis: Correlation and multiple linear regression were used to examine the association between variables. Results: Models indicated that changes in efficacy and feeding knowledge accounted for a significant portion of the variance in nutrition education changes (R[superscript 2] = 0.59) and family communication changes (R[superscript 2] = 0.29). A reduction in misconceptions was significantly associated with improved feeding practices (beta = 0.71; P less than 0.01; R[superscript 2] = 0.40). Conclusions and Implications: Understanding child care providers' knowledge and beliefs regarding their role in children's healthful eating is an essential component of child care-based obesity prevention initiatives. Training should assess and address provider efficacy and misconceptions as well as educate providers about evidence-based practices related to child feeding, nutrition education, and family communication. (Contains 5 tables.)