Cerebral oxygen consumption accounts for around 20% of the whole-body oxygen consumption. In the perioperative period,monitoring the adequacy of cerebral perfusion and oxygen delivery is desirable, since they can be compromised by several factors related to surgery and anaesthesia Cerebral oximeters are monitoring devices based on near infrared spectroscopy (NIRS) providing a continuous and non-invasive assessment of cerebral oxygenation. Cerebral oximetry is commonly adopted in cardiac surgery, with the widest application in aortic arch procedures and pediatric congenital heart surgery.There is growing interest in its application in non-cardiac surgery settings. Whilst the evidence for a role in impacting patient outcomes is still not completely clear even in cardiac surgery, cerebral oximetry can be a useful adjunct in perioperative monitoring and in hemodynamic management, provided that it is interpreted in the context of other physiological variables.