Ms J is a 52-year-old woman with severe obesity and depression, anxiety, and osteoarthritis who has not been able to sustain weight loss through dieting and is now considering having weight loss surgery. She would like to know the long-term effects of surgery, including its psychological consequences. The article discusses the consequences of the 2 most commonly performed bariatric procedures, Roux-en-Y gastric bypass and laparoscopic adjustable gastric banding, and their effects on weight loss, comorbidities, psychological function, and overall quality of life. Evidence suggests average weight loss at 10 years after surgery of 25% and 13%, respectively. The risk of perioperative mortality varies with patient factors and surgeon experience but is typically less than 1% with experienced surgeons. Roux-en-Y gastric bypass has a higher complication rate than laparoscopic adjustable gastric banding. Many obesity-related comorbidities such as diabetes and hypertension resolve or improve with weight loss, and quality of life generally improves in parallel with weight loss. However, depression and anxiety, as Ms J experiences, do not necessarily improve as a result of surgery.