Summary A case of recurrent Staph. aureus hemolyticus pneumonia and empyema treated with novobiocin (Cathomycin) has been described. The recurrence followed the use of penicillin, Chloromycetin, and erythromycin. To our knowledge, this is the first report in the pediatric literature of this disease in early infancy treated with this antibiotic. Novobiocin was administered in a dosage of 50 mg. per kilogram daily. It was given as a powder every six hours, mixed with formula or fruit. Despite the continuous administration of the drug in adequate dosage for nineteen days, there were no side effects or toxic manifestations of any sort. Since the staphylococcus has acquired increasing resistance not only to penicillin but to other antibiotics as well, the search for newer and more potent drugs against this ubiquitous and ever-dangerous organism must be unceasing.