OverviewSepsis is a potentially life-threatening complication of an infection and involves a complex array of inflammatory responses. Sepsis is usually caused by bacterial, viral, or fungal infections that are likely to develop into pneumonia, abdominal infections and kidney infections. Sepsis has gained increasing publicity in recent years and is now a strong focus of clinical education following the launch of the ‘Surviving Sepsis’ campaign. Paramedics need to understand the pathophysiological process associated with sepsis, and how these may present in patients.