During the beginning of the 1970s, major changes occurred in Costa Rica in the treatment of streptococcal throat infections. Because of poor compliance with regimens using orally administered agents, intramuscular administration of benzathine penicillin was selected as the standard treatment and throat cultures were eliminated as a prerequisite for prescribing antibiotics. A decline in the incidence of rheumatic fever then occurred. We believe that similar health intervention could be applied in other developing countries.