This document reviews literature on using prehospital lactate measurement to identify sepsis patients and initiate early treatment. It finds that lactate levels above 4mmol/L are strongly associated with increased mortality and organ dysfunction in sepsis. One small trial found that paramedic identification of severe sepsis patients based on lactate testing led to earlier treatment and a lower mortality rate of 13.6% versus 26.7% in patients who self-presented to the emergency department. However, larger randomized controlled trials are still needed to definitively establish whether prehospital lactate testing can reduce sepsis mortality rates.