This review summarizes further work characterizing the nature of the Na/glucose cotransporter and the Na/H exchanger, together with studies that question the central role of Cl secretion as the main driving force for fluid secretion. The integration of the large number of hormones, neurotransmitters and peptides involved in modulating small intestinal water and electrolyte transport into a coherent model is proving to be extremely complex. Definition of the role of single factors is currently being undertaken and this review highlights recent advances in this area. The role of diet in this respect is particularly interesting and potentially important clinically. The coordinated behavior of smooth muscle and secretory processes in small intestine is still being elucidated, but it is already clear that it is a process of some sophistication and subtlety. One endpoint of a better definition of the pathophysiology of diarrhea is better clinical management. There are therefore reviews on improved oral rehydration solutions for gastroenteritis, better management of fluid and electrolyte balance in short bowel syndrome, and recent advances in the pharmacologic treatment of diarrheal disease.