Inclusion Criteria:  Age >18 years Clinically suspected or proven infection resulting in principal reason for acute illness SBP <90mmHg or MAP <65mmHg and measured serum lactate of >2mmol/L at the time of eligibility assessment Hospital presentation within last 12 hours  Exclusion Criteria:  >1500ml of intravenous fluid prior to screening Clinically judged to require immediate surgery (within one hour of eligibility assessment); Immediate (< 1hour) requirement for central venous access Chronic renal replacement therapy Known allergy/adverse reaction to norepinephrine Palliation / end of life care (explicit decision by patient/family/carer in conjunction with clinical team that active treatment beyond symptomatic relief is not appropriate) Previous recruitment in the trial Patients with permanent incapacity