20% of the normal population are nasal carriers of Staphylococcus aureus (Sa), and the carrier rate is even higher in insulin dependent diabetics, intravenous drug addicts, patients on haemo- and peritoneal dialysis, and HIV infected patients. Nasal Sa carriers have an increased risk of Sa infections following invasive therapy. Mupirocin, a novel topical antibiotic, is highly effective against nasal Sa. A number of studies indicate that it may reduce the incidence of Sa infections in dialysis patients, however experience with other categories of patients is sparse. Surgical wound infection with Sa is a particularly serious complication after implantation of foreign body material, e.g. artificial joints. There is a need for controlled clinical trials to test the efficacy of mupirocin in eradicating Sa in these types of patients. Uncritical use of mupirocin for topical treatment of wounds should be avoided in order to prevent development of resistance.