Bariatric surgery is an increasingly utilized treatment for the growing number of individuals with extreme obesity. Early results tend to be strong, with patients losing 20-30% of their initial body weight in the first 6-18 months after surgery and experiencing improvements in obesity-related comorbidities. These outcomes, however, are not universal. Approximately 25% of patients experience suboptimal weight losses or significant weight regain within the first few postoperative years. Reasons for this weight regain are not fully understood, but likely involve both physiological processes as well as psychosocial and behavioral factors. Evidence suggests that preoperative psychosocial status and functioning can contribute to suboptimal weight losses and/or postoperative psychosocial distress. Work in this area has focused on formal psychopathology and with particular focus on mood disorders as well as binge eating disorder (BED). Individuals who present for bariatric surgery also have high lifetime rates of substance use disorders. Mood and substance use disorders, as well as BED, share common features of impulsivity, although authorities in these fields often use complementary, yet different terms to describe the phenomenon. The inability to control impulses, whether to eat in response to the toxic food environment or more generally, may play a central role in the experience of suboptimal outcomes after bariatric surgery. The goal of this study is to evaluate the relationship between psychopathology, disordered eating, and impulsivity (measured by clinical interview, self-report measures, and objective testing) on changes in weight and psychosocial status in the first two years after bariatric surgery. We predicted that individual assessments of these constructs, as well as composite measures, will be associated with smaller postoperative weight losses as well as greater caloric intake, less physical activity, and more psychosocial distress two years after surgery. Results of this study could provide important information on the psychosocial and behavioral aspects of bariatric surgery that could have a significant impact on the preoperative screening and postoperative care for the hundreds of thousands of individuals who undergo bariatric surgery each year.