Despite remarkable advances in the knowledge of infection and human response to it, sepsis continues to be one of the most common challenges surgeons and critical care providers face. Surgeons confront the problem of infection every day, in treating established infections or reacting to a consequence of surgical intervention. Infections after surgery continue to be a problem despite massive efforts to prevent them. Patients rely on the surgeon’s ability to recognize infection and treat it. Also, preventing nosocomial infection and antibiotic resistance is a primary responsibility. This article describes diagnostic and therapeutic measures for sepsis in the perioperative surgical patient.