The aim of this study was to investigate the timing and course of investigation and diagnosis in children with acute arterial ischaemic stroke (AIS) and factors influencing this using a retrospective case-note review. Participants comprised 50 children (26 males, 24 females; median age at presentation 3 y 4 mo, range 2 mo-16 y 10 mo). Although all had brain infarction, symptoms resolved in less than 24 hours in 21 children (transient ischaemic attack [TIA] group). Thirty-seven children saw a doctor within 6 hours of the attack; 32 did not see a paediatric neurologist until after 24 hours. Initial neuroimaging (computed tomography or magnetic resonance imaging) occurred in less than 6 hours in 13/46 children and in more than 24 hours in 18/46 children. Brain magnetic resonance imaging occurred in more than 24 hours in 43/47 children. Time to clinical diagnosis (data available on 42 children) was less than 6 hours in 14 children, 6 to 12 hours in six, 12 to 24 hours in eight, and more than 24 hours in 14 children. In multiple regression analysis, patients with stroke were more likely to have shorter time to diagnosis than those with TIA. Our results show that most children with acute AIS are seen within 6 hours but definitive imaging and specialist assessment take more than 24 hours. Time to diagnosis is significantly longer in children with TIA (p=0.001). Trials of acute treatment being designed for childhood AIS will require rapid transfer to tertiary centers and access to definitive neuroimaging, but these data suggest that this will challenge existing practice.