DISTURBING EPIDEMIOLOGICAL DATA: Over the past decade there has been a continuous progression in the percentage of Staphylococcus aureus strains resistant to methicillin (MRSA), a slight progression in coagulase-negative staphylococci strains resistant to methicillin and a spectacular progression of enterococci resistant to glycopeptides, not only in hospitals but also in intensive care settings. The increase in nosocomial septicemia is currently a major patient safety issue. HIGHER MORTALITY IN BACTEREMIC PATIENTS: The excess mortality globally observed in cases of bacteremia (compared with patients without bacteremia) is markedly enhanced with regard to secondary bacteremia. Bacteremia is responsible for a significant increase in the overall duration of hospitalization. PROGNOSTIC FACTORS OF STAPHYLOCOCCI BACTEREMIA: The mortality rate is significantly higher in patients in whom initial therapy was inappropriate compared with those in whom it was adequate. The isolation of MRSA strains is a negative prognostic factor. PATIENTS AT RISK OF MRSA BACTEREMIA: Independent risk factors for MRSA bacteremia include prior exposure to antibiotics, a nosocomial origin, a history of hospitalization within the 6 preceding months, and the presence of a decubitus ulcer. To avoid MRSA bacteremias related to catheters, alternatives should be found to their use, all hygiene rules should be carefully respected, the insertion point should be carefully disinfected and protected, and the catheter should be removed as rapidly as possible.