Sepsis is a systemic inflammatory response to microbial infection that leads to organ dysfunction and has a mortality rate of 15–25%. Septic shock is defined as sepsis with hypotension requiring vasopressors, with in-hospital mortality approaching 30–50%. Sepsis is now defined as infection associated with organ injury distant from the infection site. Sepsis has been recognized since ancient times and its definition has evolved, with the 1991 SIRS criteria being widely used. However, recent efforts aim to eliminate the SIRS requirement as it is too broad for sepsis definition. Sepsis is now defined as infection associated with organ injury. Sepsis is a complex condition involving inflammation, immune suppression, endothelial dysfunction, coagulation, and neurological disturbances. Despite increased understanding, sepsis outcomes remain slow to improve. Sepsis is a major global health issue with high mortality, especially in low- and middle-income countries. The incidence of sepsis is increasing in high-income countries, but mortality rates are declining due to earlier recognition and better treatment. Sepsis is a systemic disorder affecting all organs, with six main types of organ dysfunction: neurological, pulmonary, cardiovascular, renal, haematological, and hepatic. Diagnosis of sepsis is based on clinical signs, symptoms, and laboratory findings. Septic shock is defined by persistent hypotension despite adequate fluid resuscitation. Biomarkers such as procalcitonin can help distinguish sepsis from non-infectious conditions and guide antibiotic use. Prevention of sepsis involves reducing infections through vaccination, good hygiene, and treating local infections. Hospitalized patients are at higher risk, requiring strict infection control measures. Sepsis remains a significant challenge in healthcare, with ongoing research into effective treatments and prevention strategies.Sepsis is a systemic inflammatory response to microbial infection that leads to organ dysfunction and has a mortality rate of 15–25%. Septic shock is defined as sepsis with hypotension requiring vasopressors, with in-hospital mortality approaching 30–50%. Sepsis is now defined as infection associated with organ injury distant from the infection site. Sepsis has been recognized since ancient times and its definition has evolved, with the 1991 SIRS criteria being widely used. However, recent efforts aim to eliminate the SIRS requirement as it is too broad for sepsis definition. Sepsis is now defined as infection associated with organ injury. Sepsis is a complex condition involving inflammation, immune suppression, endothelial dysfunction, coagulation, and neurological disturbances. Despite increased understanding, sepsis outcomes remain slow to improve. Sepsis is a major global health issue with high mortality, especially in low- and middle-income countries. The incidence of sepsis is increasing in high-income countries, but mortality rates are declining due to earlier recognition and better treatment. Sepsis is a systemic disorder affecting all organs, with six main types of organ dysfunction: neurological, pulmonary, cardiovascular, renal, haematological, and hepatic. Diagnosis of sepsis is based on clinical signs, symptoms, and laboratory findings. Septic shock is defined by persistent hypotension despite adequate fluid resuscitation. Biomarkers such as procalcitonin can help distinguish sepsis from non-infectious conditions and guide antibiotic use. Prevention of sepsis involves reducing infections through vaccination, good hygiene, and treating local infections. Hospitalized patients are at higher risk, requiring strict infection control measures. Sepsis remains a significant challenge in healthcare, with ongoing research into effective treatments and prevention strategies.