In recent years, several risk factors for adverse outcome in patients undergoing anaesthesia have been identified. Besides human errors, cardiovascular and respiratory complications are associated with substantial morbidity. Assessment of complications has promoted the introduction of basic physiological monitoring in clinical practice. Whether monitoring directly affects outcome is not proven; however, circumstantial evidence suggests that basic cardiorespiratory monitoring decreases the incidence of serious accidents. Prevention of hypothermia also reduces anaesthesia-related morbidity. Measurement of body temperature is mandatory, and active warming is a simple, effective technique to avoid hypothermia. Evidence is growing that patients with known or suspected coronary artery disease should be treated with beta blockers perioperatively. Whether the type of anaesthesia-ie, general or regional-is relevant to perioperative mortality remains unclear. In subgroups of patients at high risk, neuraxial anaesthesia reduces the rate of respiratory and cardiovascular complications.