Introduction In rat stroke models, sphenopalatine ganglion stimulation up to 24h after stroke onset augments cerebral blood flow, reduces infarct volume and improves neurological deficits. The ischaemic stroke system 500 has been designed to stimulate the sphenopalatine ganglion in humans. Objectives (1) To determine the safety and tolerability of the ischaemic stroke system 500 in acute ischaemic stroke within 24h of stroke onset. (2) To determine the effectiveness of ischaemic stroke system 500 in acute ischaemic stroke treatment. Design/Methods Implant for augmentation of cerebral blood flow trial-1 is a multi-national open-label study in patients of acute ischaemic stroke in the anterior circulation with National Institutes of Health Stroke Scales 7-20. The treatment initiation will be within 24h of stroke onset. The ischaemic stroke system is implanted adjacent to the sphenopalatine ganglion via the greater palatine canal using local anaesthesia and a minimally invasive approach. The treatment protocol is constituted as 3-4h of daily stimulation over 5-7 days. Conclusions The implant for augmentation of cerebral blood flow trial-1 will determine the safety and tolerability of the ischaemic stroke system 500 in acute ischaemic stroke as reflected by the incidence of adverse events.