Severe pathological changes in the cardiac valves are often observed at an early age in children in the developing countries. Mitral stenosis is best managed by closed commissurotomy. However, mitral insufficiency, aortic insufficiency and tricuspid lesions may lead to life-threatening hemodynamic effects which necessitate valve replacement. This differs from experience in the developed countries where surgery for rheumatic valvular disease is limited to the adult. Our experience includes 33 children aged 5 to 16 years. Twenty-four children underwent single valve replacement, eight had two valves replaced and one had triple valve replacement. All were classified Grade IV or late Grade III (New York Heart Association). Four children had to be operated on despite known rheumatic activity. Two children in shock and pulmonary edema underwent emergency operation. There were two hospital deaths and eight late deaths. Patients have been followed for up to eight years. Twenty children are now classified as Grade I and lead completely normal lives and the remaining three are classified as Grade II. Postoperative catheterization studies have documented improvement from severe preoperative hemodynamic changes to near normal values at rest after operation. The cardiothoracic ratio has decreased impressively. We conclude that the natural history of rheumatic heart disease in children with severely damaged heart valves is favorably modified by valve replacement.