Sepsis is a common condition caused by the body’s immune and coagulation systems being ‘switched on’ by the presence of infection, either through bacteria or viruses in the blood. If untreated, sepsis can be life-threatening and is a leading cause of death in hospital patients worldwide. However, awareness of sepsis is low. This article provides an overview of the important role played by nurses in acute hospital settings in the early identification and treatment of suspected sepsis in frail older patients, and in escalating the care and management of deteriorating patients. It also explores recommendations in the 2016 National Institute for Health and Care Excellence guideline on sepsis recognition, diagnosis and early management.