The use of steroids in septic shock remains controversial. The purpose of this study is to determine whether hydrocortisone decreases 28-day mortality in patients with septic shock. The primary end point will be 28-day mortality in all the non-responders to ACTH (< or = 9 mcg/dl or 250 nmol/L post ACTH). Secondary endpoints will be 28 day all cause mortality in the total group and in responders, ICU and hospital mortality, one year mortality, organ system failure reversal especially shock, and duration of ICU and total hospitalisation.