Rotavirus is the most common cause of severe acute diarrhea, responsible for 30 to 40 deaths of children each year in France. In order to decrease both mortality and morbidity, vaccines have been designed first from attenuated bovine strains, then from monovalent simian strains, and more recently from reassortant rhesus strains. The live tetravalent human-rhesus reassortant vaccine (RRT-TV) has been shown to be protective in the United States, Finland, and Venezuela despite different environments, in prospective double-blind studies. This vaccine, as the natural infection, decreases by 50% the risk of acute rotavirus diarrhea and by 70 to 100% the risk of severe diarrhea with dehydration. At the present time, its cost limits its use to developed countries. It was put on the market in the United States in October 1998. The challenge is now to make it available in developing countries.