Enhanced recovery after surgery (ERAS) programs are a multidisciplinary approach in the perioperative care of the patient undergoing major surgery, including pre, intra and postoperative measures, based on the actual evidence published in literature (evidence-based medicine), to improve the postoperative recovery of the patient. ERAS protocols have been widely developed in colorectal surgery, but, given their excellent results, new protocols and guidelines have been developed in other surgical fields, including abdominal and extra-abdominal areas. In the last decade, several ERAS protocols have been implemented worldwide in bariatric surgery, confirming their safety and advantages of ERAS approaches, even on morbidly obese patients. The aim of this book is to update the actual evidence about ERAS protocols on bariatric surgery, analysing separately the different components and multidisciplinary approach of the ERAS programs.