Ninety-two children with rheumatic heart disease were studied clinically, and through a post-diagnosis surveillance period of varying duration over a 10-year period. The logistics and effectiveness of secondary penicillin prophylaxis, administered monthly, were assessed during the surveillance period. Eighty-one (88%) of the 92 children were seen for the first time with already established rheumatic heart disease. Mitral insufficiency was the major functional defect in these children whose mean age was 8.6 years. There was a high default rate of just under 50% among children referred to the surveillance clinic. Socio-economic inadequacies were found to be major factors in the high default rate. Regular monthly parenteral penicillin was found to be effective in reducing recurrence of rheumatic fever and maintaining good health in these children.