Background: The 1997 A.S.P.E.N. Research Workshop was held at the annual meeting in San Francisco, on January 26, 1997. The workshop focused on advances in clinical and basic research involving the interface between nutrient and luminai gastroenterology. Methods: Presentations on the geneticregulation of gastrointestinal development, the molecular biology of small intestinal adaptation, the effect of nutrition support on intestinal mucosal mass, the relationship between nutrition and gastrointestinal motility, nutrient absorption, and gastrointestinal tract substrate metabolism were made by the preeminent leaders in the field. Results: The investigators presented an insightful analysis of each topic by reviewing data from their own laboratories and the published literature. Conclusions: This workshop underscored the important interactions between nutrition and luminal gastroenterology at the basic science, metabolic/ physiologic, and clinical levels. The integration of presentations from the different disciplines provided a unique interaction of information and ideas to advance our understanding of nutrition and gastrointestinal tract. Copyright & 1998 by the American Society for Parent eral ami Enterai Nutrition.