In daily clinical practice the diagnosis of sepsis is imprecise and often delayed. In part, this is because the diagnosis is based on a clinical picture of signs and symptoms. This basis has significant implications, as there is evidence that early events in sepsis may determine outcome. A more objective set of measurements for confirming the diagnosis of sepsis has long been sought. Several sepsis biomarkers have been evaluated and shown to have a moderate degree of sensitivity and specificity for diagnosing the presence of bacterial infection. Efforts are now being directed toward evaluating the utility of biomarker profiles, containing multiple markers, for risk assessment and diagnosis in patients with suspected sepsis.