Preface: Over the last decade, bariatric surgeons have witnessed more dramatic advances in the field of bariatric surgery than in the previous 50 years of this relatively young discipline. These changes have certainly been fueled by the great obesity epidemic beginning in the 1970's which created the demand for effective treatment of severe obesity and its co-morbidities. The gradual development and standardization of safer, more effective, and durable operations such as Roux-en Y gastric bypass (RYGB), biliopancreatic diversion, duodenal switch, and adjustable gastric banding account for the first wave of advances over the last decade. More recently, the advent of minimally invasive surgery in the mid 1990's accounts for the second wave of major advances. Fifteen years ago, fewer than 15,000 bariatric procedures (mostly vertical banded gastroplasty) were performed each year in the U.S. and all were performed with a laparotomy requiring nearly a week of hospitalization and 6 weeks of convalescence. Mortality rates exceeding 2 percent and major morbidity exceeding 25 per cent was the norm. It later became apparent that the laparotomy itself accounted for much of the morbidity of bariatric surgery contributing to major impairment in postoperative cardiopulmonary function leading to atelectasis, pneumonia, respiratory failure, heart failure, and lengthy stays in the intensive care unit for a significant subset of patients. Furthermore, wound complications including infections, seromas, hernias and dehisences were the norm rather than the exception. Hernias were so common (20-25 per cent) that they were often considered the second stage of a bariatric procedure. Today, over 200,000 bariatric procedures are performed each year in the U.S. and nearly twice that figure worldwide. Nearly all gastric banding procedures, an estimated 75 per cent of RYGB procedures, and even some BPD procedures are performed laparoscopically indicating that the laparoscopic approach has been widely adopted in bariatric surgery. The dramatic reduction in postoperative pain, hospital stay to 1-3 days, recovery to 2-3 weeks, incidence of intensive care utilization to 50 per cent). Laparoscopic cholecystectomy, Nissen fundoplication, and bariatric procedures represent the major triumphs thus far of the laparoscopic revolution. Perhaps, bariatric operations represent the best application of minimally invasive procedures because avoidance of an extensive laparotomy in the high-risk bariatric population provides the greatest relative benefit. We hope that you encounter as much enjoyment reading "Minimally Invasive Bariatric Surgery" as we have had writing it! Now, on to the next revolution in bariatric surgery! Phil Schauer, MD Bruce Schirmer, MD Stacy Brethauer, MD