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. One of the main keypoints in the multidisciplinary approach is a correct management of postoperative pain. Adequate analgesia implies lower morphine requirements and facilitates early postoperative mobilization. Consequently, lower postoperative ileus and earlier oral intake can be achieved. Altogether, this leads to an improvement of the overall quality of life. Multimodal analgesia is one of the main tools employed for these aims. It consists of the administration of different analgesic drugs by different ways, reducing the risk of toxicity and the appearance of adverse effects. In addition, the different analgesic methods used provide a synergistic effect, maximizing the analgesic result. The aim of this book is to update the actual evidence about ERAS protocols on different surgical approaches, analyzing the different analgesic schemes used in different approaches, all of them including the principle of multimodal analgesia.