Staphylococcus aureus strains are present in the nose of 30% of healthy humans and are responsible for skin and soft tissue infections. Deep seated infections secondarily occurred such as osteomyelitis or infective endocarditis. New toxin-associated clinical entities have been recognized such as the toxin shock syndrome, the staphylococcal scarlet fever, the staphylococcal scalded skin syndrome or the necrotising pneumonia. This later syndrome is associated with Panton Valentine leukocidin producing strains. It occurs mainly in children and has a lethality of 75%. New antibiotic resistances are also emerging, for vancomycin in hospital-acquired infections and for methicillin in community-acquired infections.