Severe sepsis and septic shock are frequent pathologies accounting for approximately 11% of all admissions in intensive care units (ICU). In the United States, between 1979 and 2000 the incidence of sepsis increased by 8,7% annually and septic shock) remains the second most frequent cause of death in non-coronary ICU. Although our understanding of the host defense mechanisms against infections and of the pathogenesis of septic shock have progressed during the last decade, these progresses have not yet yielded the anticipated advantages. Recent new therapeutic approaches, especially early-goal directed therapy, activated protein C (drotrecogin alpha activated), moderate doses of corticosteroids and intensive insulin therapy have given encouraging results.