Enhanced recovery after surgery was developed based on the question "Why is the patient in hospital?" and is evolving in the context of multimodal perioperative care programmes with documented major benefits with respect to the need for hospitalisation and the risk of complications. Despite being a worldwide success, future challenges to improvements include patient and procedure-specific modification of inflammatory/immunological stress responses, improvement of post-discharge recovery, closing the knowing-doing gap between scientific evidence and clinical practice, and improving research design strategies.