PROJECT SUMMARY/ABSTRACT Food insecurity is common among people with obesity and is associated with suboptimal outcomes in behavioral weight loss (BWL) treatment. However, we do not yet have evidence of treatment approach to address food insecurity and obesity that can target multiple barriers including cost, access, skills, knowledge, and behavior. improving The overarching goal of this application is to reduce socioeconomic disparities in obesity by patients' abilities to afford and access nutritious foods during BWL treatment. To accomplish thisgoal, the proposed 3-group, parallel design, randomized controlled trial will assign 258 adults with obesity and food insecurity to BWL-Alone (including standard-of-care referral and connection with community food resources; delivered, vouchers provided of n=86); BWL plus food supplementation with either food vouchers (BWL+VOUCHER; n=86); home- medically tailored groceries consistent with BWL recommendations (BWL+HOME; n=86). Food and HOME will be provided for the first 24 weeks o treatment. All groups will have BWL treatment for 52 weeks per CMS guidelines. Assessments will be conducted at baseline, and weeks 12, 24 (end food supplementation), and 52 (end of BWL treatment). f Our aims are to test the hypothesis that BWL+VOUCHER and BWL+HOME will result in greater weight loss (percent of initial weight) at 24 weeks than BWL-Alone. A secondary aim is to determine if BWL+VOUCHER and BWL+HOME result in better weight loss at 52 weeks compared to BWL-Alone. Additional secondary aims are to examine treatment differences in health-related quality of life and self-reported and objective measures of dietary quality. The expected outcome of this study is to demonstrate feasible food support interventions that can be used within health care systems to address social determinants of health and achieve better health equity, and is well aligned to contribute to the mission of the National Institute of Nursing Research.