BACKGROUND: Among patients who express interest in bariatric surgery, dropout rates from bariatric surgery programs are reported as high as 60%. There is a lack of understanding how we can better support patients to obtain treatment of this serious chronic disease. METHODS: Semi-structured interviews with individuals who dropped out of bariatric surgery programs from three clinical sites were conducted. Transcripts were iteratively analyzed to understand patterns clustering around codes. We mapped these codes to domains of the Theoretical Domains Framework (TDF) which will serve as the basis of future theory-based interventions. RESULTS: Twenty patients who self-identified as 60% female and 85% as non-Hispanic White were included. The results clustered around codes of perceptions of bariatric surgery, reasons for not undergoing surgery, and factors for re-considering surgery. Major drivers of attrition were burden of pre-operative workup requirements, stigma against bariatric surgery, fear of surgery, and anticipated regret. The number and time for requirements led patients to lose their initial optimism about improving health. Perceptions regarding being seen as weak for choosing bariatric surgery, fear of surgery itself, and possible regret over surgery grew as time passed. These drivers mapped to four TDF domains: environmental context and resources, social role and identity, emotion, and beliefs about consequences, respectively. CONCLUSIONS: This study uses the TDF to identify areas of greatest concern for patients to be used for intervention design. This is the first step in understanding how we best support patients who express interest in bariatric surgery achieve their goals and live healthier lives.