Sleeve gastrectomy, gastric bypass, gastric banding, and duodenal switch are the most common bariatric procedures performed worldwide. Ninety-five percent of bariatric operations are performed with minimally invasive laparoscopic technique. Perioperative morbidities and mortalities average around 5% and 0.2%, respectively. Long-term weight loss averages around 15% to 25% or about 80 to 100 lbs (40-50 kg). Comorbidities, including type 2 diabetes, hypertension, dyslipidemia, sleep apnea, arthritis, gastroesophageal reflux disease, and nonalcoholic fatty liver disease, improve or resolve after bariatric surgery.