The purpose of this study is to externally validate previously developed prognostic models predicting functional outcome 100 days after acute ischaemic stroke. Data prospectively collected from 1,754 patients were used to develop two models predicting functional dependence (Barthel Index < 95) and mortality. Both models were internally validated and calibrated. A prospective multicentre study is being performed to validate the developed models with an independent data set. On admission to one of 15 participating hospitals, all patients with acute ischaemic stroke will be registered prospectively in the co-ordinating centre. Within 72 hours, potential predictive variables will be assessed. 1,975 patients will have to be recruited to achieve a power of 95% at the 5% significance level. The resulting prognostic models will be useful for adequately stratifying treatment groups in clinical trials and to accurately predicting the outcome variable.