The King's College Hospital (KCH) Acute Stroke Unit (ASU) was set up in January 1994 in order to provide acute management for patients admitted with stroke and to undertake biomedical research. Of 206 patients admitted to KCH with a stroke or suffering an in-hospital stroke, 141 (68%) patients were admitted to the ASU over its first 6 months of operation: 120 (85%) were from the Accident and Emergency Department and 21 (15%) from other wards. Management included resuscitation and medical stabilisation, investigation, prevention of stroke complications (including aspiration, venous thrombosis, and pressure sores), rehabilitation (physiotherapy, occupational therapy, speech and language therapy), nutrition (dietetics) and initiation of secondary prevention measures (aspirin or anticoagulation, blood pressure and lipid lowering, and carotid endarterectomy). All aspects of management are driven by agreed guidelines. Patients remain under the care of the admitting physician but specific stroke management and guidance is provided by two research doctors and the unit's nurses, therapists and dietician. The unit also facilitates research into stroke pathophysiology and acute therapeutic interventions. Our experience suggests that an ASU is relatively easy to set up and may contribute to improved care. Whether ASUs improve patient survival and functional outcome, and are cost-effective, requires further study.