Staphylococcus aureus is a dreadful pathogen for mankind, causing boils, abscesses, wound infections, osteomyelitis, septicaemia, endocarditis, pneumonia, toxic shock syndrome, scalded skin syndrome, and food poisoning. The development of penicillin-, methicillin-, and vancomycin-resistant strains shows that S. aureus has an enormous adaptive power. Most methicillin-resistant strains of S. aureus (MRSA) are hospital-acquired, although an increasing number are reported to be community-acquired. A limited number of clones of MRSA have spread all over the world. Since most community-acquired MRSA can be traced back to some contact with health care, MRSA can still best be combatted by control measures in health care institutions. In this respect, the Netherlands and Scandinavian countries have been very successful so far. S. aureus has many virulence factors at its disposal: structural components, enzymes and three types of toxins. Panton-Valentine leukocidin (PVL) has received attention as a factor causing severe pneumonia with high mortality. A strain combining methicillin resistance and PVL has spread through France. Recently, the genome of an MRSA strain has been unravelled. Its structure illustrates how well S. aureus can adapt itself and acquire properties of other microorganisms. This genetic knowledge may lead to new strategies to combat S. aureus.