The intestinal tract plays a key role in the body's response to injury and infection, both as a barrier to poisons and as a substrate processing station for the liver and other organs. Like the kidneys, heart, lungs, and liver, the gut is susceptible to dysfunction and possibly failure in certain critically ill patients. This failure is far more complex than simple ileus from bowel inactivity and disuse. Optimal support for the intestinal tract during catabolic states requires provision of appropriate nutrition, support of other organs, aggressive management of wounds, and possibly the use of newer growth factors which may have trophic effects on the gut mucosa. Enteral nutrition is currently the preferred method of feeding and should be instituted whenever feasible.