Oral rehydration therapy (ORT) with glucose-electrolyte solutions has been considered to be one of the greatest therapeutic advances of this century. ORT is effective in acute diarrheal disease of diverse etiology. The most widely used oral rehydration solution (ORS) worldwide is that recommended by the World Health Organisation (Na 90, K 20, glucose 111 and citrate 10 mmol/L). Attempts to improve the efficacy of ORS have been made by using complex substrates (rice and other cereals) in place of glucose, and by reducing osmolality by decreasing glucose and sodium concentrations in monomeric ORS. ORS may have wider applications in the management of patients with the short bowel syndrome and in post-surgical patients.