Diarrheal diseases are a serious public health problem in the Gaza Strip, being the most important cause of hospitalization in infants and responsible for about half of postneonatal deaths, Oral rehydration therapy using oral rehydration solution (ORS), a formula recommended by WHO, has been proven effective in the treatment of dehydration in acute childhood diarrhea. The availability of a well-organized health service in Gaza provided an excellent opportunity to institute a large-scale project to evaluate the effectiveness of early ORS therapy in reducing diarrhea-related hospital admissions, mortality and malnutrition. A 3-year program was started in 1979, encompassing all community health centers and including intensive community education in the use of ORS. Compared with the prestudy year 1977, diarrhea-related hospital admissions were reduced by 35.3% in 1980 and 42.0% in 1981; hospital deaths from diarrheal diseases were reduced 34.4 and 37.4% in 1980 and 1981, respectively. Total deaths in the 0- to 3-year age-group were reduced by 28.7% in 1980 and by 41.7% in 1981. Diarrheal mortality was reduced by 35.6% in 1980 and 53.2% in 1981. This study succeeded in establishing active community and family participation.