Project Summary This Patient-Oriented Career Development Award (K23) is designed to promote the development of Dr. KayLoni Olson as an independent, clinical research scientist focused on developing interventions to address factors that contribute to individual variability and poor outcomes in behavioral weight management. Overweight and obesity remain a major threat to public health and contribute significantly to health care costs in the United States. Standard behavioral weight management (SBT) facilitates clinically significant weight loss for many individuals but there is variability in treatment outcome. High weight and shape concern (WSC) is associated with less weight loss among women in behavioral weight management. One potential explanation for this relationship is that individuals with High WSC have more frequent negative thoughts about weight/shape which lead to overeating episodes. We therefore propose to use the Obesity-Related Behavioral Intervention Trials guidelines to refine an empirically-supported WSC treatment (the Body Project: BP) to increase suitability for adult women with overweight or obesity and enhance treatment effects. The protocol will be iteratively refined using exploratory sequential mixed methodology to more powerfully target WSC among women with overweight or obesity and to ensure acceptability to the target sample (Aim 1). The revised protocol will be tested in a randomized pilot trial to evaluate effects when combined with SBT (Aim 2). For the pilot trial, 60 women with overweight or obesity who report High WSC and want to lose weight will be recruited. They will be randomized to either a four-week WSC intervention (modified-BP) or a four-week, education-only control condition. All participants will then receive 24-week SBT. WSC and body weight will be assessed at baseline, 4 weeks, and after 24 weeks of weight loss. EMA will be utilized to evaluate treatment effects on negative weight/shape-related thoughts and overeating episodes throughout treatment. To conduct this project the applicant will complete a rigorous, targeted training program to acquire key skills necessary for the success of the project and to prepare the applicant for independence as an obesity researcher. Key areas for growth including 1) behavioral intervention development, 2) obesity stigma as a contributor to WSC, 3) ecological momentary assessment, 4) advanced quantitative methods to assess treatment outcomes, moderating and mediating factors, and 5) professional development. This training will be conducted under the primary mentorship of Dr. Rena Wing, with co-mentors Drs. Rani Elwy, Rebecca Puhl, Graham Thomas, Shira Dunsiger, and contributor Dr. Meghan Butryn. The skills acquired map directly onto elements of the proposed project but also position the applicant to expand her program of research in innovative directions. This mentorship team, in combination with the infrastructure and resources available through The Miriam Hospital and the Weight Control and Diabetes Research Center, represent the ideal environment to accomplish the applicant?s training goals, foster professional development and establish the applicant?s autonomy as an independent clinical obesity researcher.