Introduction: The optimal management of post stroke cognitive impairment remains controversial. These joint European Stroke Organisation (ESO) and European Academy of Neurology (EAN) guidelines provide evidence-based recommendations to assist clinicians in decision making around prevention, diagnosis, treatment, and prognosis. Methods: These guidelines were developed according to ESO standard operating procedure and the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and, where possible, meta-analyses of the literature, assessed the quality of the available evidence, and made specific recommendations. Expert consensus statements were provided where insufficient evidence was available to provide recommendations based on the GRADE approach. Results: There was limited randomised controlled trial evidence regarding single or multicomponent interventions to prevent post stroke cognitive decline. Interventions to improve lifestyle and treat vascular risk factors may have many health benefits but a beneficial effect on cognition is not proven. We found no evidence around routine cognitive screening following stroke but recognise the importance of targeted cognitive assessment. We described the accuracy of various cognitive screening tests but found no clearly superior approach to testing. There was insufficient evidence to make a recommendation for use of cholinesterase inhibitors, memantine or cognitive rehabilitation for post stroke dementia. We made a weak recommendation against using the nootropics actovegin and cerebrolysin, but quality of evidence was very low. There was limited evidence on the use of prediction tools for post stroke cognitive syndromes (cognitive impairment, dementia and delirium). The association between post stroke cognitive impairment and most acute structural brain imaging features was unclear. Conclusions: These guidelines have highlighted fundamental areas where robust evidence is lacking. Further randomised controlled trials are needed and we suggest priority areas for future research.