Sepsis is a potentially life-threatening condition triggered by infection that is responsible for an estimated 48,000 deaths in the UK each year. Its pathophysiology is complex, its symptomology non-specific and its clinical presentations extremely varied. Despite numerous campaigns to raise awareness of sepsis, it still goes undetected. In 2024, the National Institute for Health and Clinical Excellence revised its guideline on sepsis and the UK Sepsis Trust published the seventh edition of its Sepsis Manual. This article discusses the pathophysiology of sepsis and how emergency nurses should assess and manage patients with suspected sepsis. It describes the tools available to them, including the National Early Warning Score 2 and the Sepsis 6, and emphasises the importance of early antibiotic administration, serial lactate measurements, source control and antimicrobial stewardship.