PROJECT SUMMARY/ABSTRACT A healthful diet during early childhood is important for healthy growth and development and contributes to the prevention of chronic diseases. Parents influence children’s dietary intake through their use of food parenting practices. Research to date shows positive associations of structure- and autonomy support- food parenting practices with healthful dietary intake and eating behaviors in children, whereas coercive controlling and indulgent practices have been associated with unhealthful dietary intake and the development of maladaptive eating behaviors over time. While research has historically evaluated parents’ “usual” approach to feeding children via questionnaires, recent evidence reveals important within- and between-day variation in use of food parenting practices across time and contexts. Parents have identified a range of momentary factors (e.g., activities, limited time, stress) in everyday family life that alter their usual approach. Parents described shifts from the use of structure- and autonomy support- feeding practices to more indulgent and controlling practices in the face of external challenges. We have recently obtained quantitative evidence of these within- and between-day shifts in food parenting practices through the use of Ecological Momentary Assessment (EMA); EMA uses short surveys delivered to hand-held devices in real time throughout the day to capture dynamic changes in behaviors across time and context. For instance, we have observed that parental stress early in the day is associated with greater use of controlling feeding practices later in the day. Our goal is to build on and extend the evidence-base of food parenting approaches for preventing poor dietary intake among children. We argue that parents’ approach to feeding varies across time and context and that a deepened understanding of the variability in food parenting practices and associated outcomes is necessary to design interventions to help parents maintain consistent use of supportive practices despite challenging circumstances. We propose to comprehensively investigate the impact of within- and between-day fluctuations in food parenting practices on children’s dietary intake overtime using a longitudinal study conducted with a sample (n=240) of racially/ ethnically- and socioeconomically- diverse parent-preschooler dyads. Data will be collected via state-of-the-art measures, including EMA and interview-led 24-hour diet recalls every 6 months for two years. The proposed study represents a significant and necessary next step to inform the development of clinic-based recommendations and public health interventions that account for- and are responsive to- momentary factors found to influence parent’s use of specific food parenting practices.