Objective: To assess the effect of cognitive assessment on the functional outcome of stroke patients and quality of life for both patients and their carers. Design: A multicentre, single-blind, randomized controlled trial. Setting and participants: Two hundred and twenty-eight stroke patients were recruited from hospital wards in three UK centres. Interventions: Patients were screened for cognitive impairment and randomly allocated to either routine care (116 patients) or routine care plus a detailed cognitive assessment (112 patients). Main outcome measures: Outcome was assessed three and six months after recruitment by an independent assessor blind to the intervention on Extended ADL, Cognitive Failures Questionnaire, General Health Questionnaire-28 for patients and carers and Carer Strain Index. Results: There was no signi”cant difference between the two groups in patients’ functional outcome, perceived cognitive ability, level of psychological distress or satisfaction with care. There was a trend for the assessment group to have lower levels of carer strain ( p = 0.06). Conclusions: The provision of information about cognitive assessment in stroke rehabilitation may decrease carer strain.