Morbid obesity is associated with an increased risk of morbidity and mortality as well as psychosocial problems and poor quality of life. The ultimate goal of bariatric surgery is not only reduced weight and reduction of co-morbidities, but also improved psychosocial functioning and quality of life. However, not all patients are successful. A systematic literature search of recent articles identified relevant variables reflecting postoperative psychosocial functioning. Most studies showed that bariatric surgery does not only lead to substantial weight reduction, but also to improvement or cure of physical as well as psychological co-morbidities. Although most studies are optimistic and report broad psychosocial improvement, a significant minority of patients do not benefit psychologically from surgery. Although there are mixed results, the overall improvements in psychosocial functioning provide additional justification for surgical treatment of morbid obesity.