Expertise in enteral nutrition (EN) is an important aspect of the skill set of the clinical gastroenterologist. Delivery of adequate EN in critically ill patients is an active therapy that attenuates the metabolic response to stress and favorably modulates the immune system. EN is less expensive than parenteral nutrition and is favored in most cases because of improvement in patient outcomes, including infections and length of stay. Newer endoscopic techniques for placing nasoenteric feeding tubes have been developed, which improve placement success and efficiency. It appears that there is an ideal window period of 24-48 h when enteral feeding should be started in critically ill patients. Most patients can be fed into the stomach, but certain groups may benefit from small bowel feeding. Protocols on how to start and monitor enteral feeding have been developed. Immune-modulating feeding formulations also appear to be beneficial in specific patient populations. The gastroenterologist is a crucial member of the multidisciplinary team for nutritional support in the intensive care unit patient, with his knowledge of gastrointestinal pathophysiology, nutrition, and endoscopic feeding-tube placement.