This document summarizes the rationale for bariatric surgery from both medical and financial perspectives. It provides evidence from several studies that bariatric surgery results in significant and sustained weight loss, resolution of diabetes and other comorbidities in the majority of patients. Cost-effectiveness analyses also indicate that while more expensive initially, bariatric surgery provides better health outcomes and is cost-effective compared to non-surgical weight loss treatments. However, more research is still needed to fully understand long-term impacts and complications.