New guidelines published in Anaesthesia deal with the perioperative care of patients with dementia. Concepts such as post-operative cognitive disorder and delirium are also discussed and their risk factors. Emphasis is on assessment, legal implications, communication and liaison with family and patients, as well as non-disorienting environments. The unproven relationship between anesthesia and dementia is discussed, as well as judicious use of anesthesia and sedatives, although again little conclusive evidence is available to choose general or regional anesthesia. The potential benefits of brain monitoring and/or regional cerebral oxygenation is reviewed. Frailty, comorbidities and polypharmacy are common issues to be managed.