The proposed study addresses obesity and health-related disparities among socioeconomically disadvantaged mothers and their young children enrolled in federally-funded home visitation programs. This is important because low-income and racial/ethnic minority mothers and their young children are especially at-risk of obesity. The lack of access to evidence-based obesity efforts further contributes to these disparities. The proposed randomized controlled trial tests the effectiveness of (1) a simple, evidence-based and ecologically relevant obesity intervention (HABITS) delivered as part of ongoing home visitation services, compared to (2) the existing home visitation curriculum without obesity-related content on mothers’ and children’s obesity risks. HABITS focuses on habit formation and modifications to the food/activity home environment to promote changes in the targeted weight-related behaviors. Participants will be 298 mothers (>50% African American; 100% meet federal poverty level) and their children (3-5yo at baseline) enrolled in our home visitation partner in central Alabama. Home visitors will be randomly assigned to deliver the home visitation curriculum with or without HABITS as part of their weekly home visits for 12 months. Assessments of mothers (weight, waist circumference, feeding practices and habit strength of targeted behaviors), children (rate of weight gain), and household environment (availability/accessibility/visibility of cues conducive to targeted food, activity and monitoring behaviors) will be conducted at enrollment, 12, and 24mo (1y post-treatment follow-up). Aim 1 (primary outcomes). To compare the effects of treatment on children and mothers’ weight outcomes at 12 and 24mo. Hypothesis 1a: Mothers receiving HABITS will have a lower weight and waist circumference than mothers receiving standard services. Hypothesis 1b: Children receiving HABITS will have slower rate of weight gain than children receiving standard services. Aim 2 (secondary outcomes). To compare the effects of treatment on maternal feeding practices, habit strength of targeted behaviors, and features of the household environment relevant to targeted behaviors at 12 and 24 mo. Hypothesis 2: Compared to standard services, HABITS will result in heathier maternal feeding practices (less fried foods and SSB; more vegetables/fruits), greater habit strength of targeted behaviors, and greater home availability/accessibility/visibility of cues that support targeted behaviors. Aim 3 (maternal/environmental transmission of children’s obesity risk). To test whether maternal and household environment variables mediate the effect of HABITS on children’s rate of weight gain at 12 and 24mo. Hypothesis 3: Maternal weight, feeding practices, habit strength of targeted behaviors, and household environment will mediate the relationship between HABITS and children’s rate of weight gain. We will further explore whether primary (Aim 1) and secondary (Aim 2) outcomes differ fo...