The SIRIO study collected detailed information on the stroke care of patients treated in neurological departments in Italy. This report refers to the baseline profile of patients. Each centre recorded the incident cases of ischaemic and haemorrhagic stroke, excluding SAH, for 1-4 months. Baseline data include demographics, risk factors, comorbidities, pre-event medications, social conditions, NIHSS and Rankin scale on entry, Barthel Index pre-event, diagnostic tests and treatments applied on entry. Overall, 3018 patients (56.7% men; mean age 72.1+/-12.2 years) with ischaemic (85.3%) or haemorrhagic stroke were hospitalised in 103 centres; 51% arrived by ambulance. Median time to hospital was 140 min (RIQ: 60-615). TOAST classification of the 2573 ischaemic strokes was: 29.4% large-artery atherosclerosis, 24.6% cardioembolic, 26.2% small vessels occlusion, 6.5% other determined causes and 13.3% undetermined. CT and/or MR were performed in all patients. Total Greenfield's comorbidity score was 5.4+/-3.5. Mean Barthel Index pre-event was 93+/-17; Rankin score on entry was 4-5 in 48% of the patients and 0-1 in 25%. Mean NIHSS on entry was 7.1+/-5.4; 52% of the patients had a NHISS <6 and 1% >22. SIRIO began giving the expected insights on the in-hospital management of stroke in Italy. Further information will be provided by the longitudinal phase of the study, which is in progress. Pre-event patient management and mode of reporting call for additional educational actions.