Background Elevated blood pressure following acute stroke is common, and yet early antihypertensive treatment is controversial. ACCESS suggested a beneficial effect of the angiotensin receptor blocker candesartan in the acute phase of stroke, but these findings need to be confirmed in new, large trials. Aims and design The Scandinavian Candesartan Acute Stroke Trial is an international randomised, placebo-controlled, double-blind trial of candesartan in acute stroke. We plan to recruit 2500 patients presenting within 30 h of stroke (ischaemic or haemorrhagic) and with systolic blood pressure ≥ 140 mmHg. The recruited patients are randomly assigned to candesartan or placebo for 7-days (doses increasing from 4 to 16mg once daily). Randomisation is performed centrally via a secure web interface. The follow-up period is 6-months. Patients are included from the following nine North-European countries: Norway, Sweden, Denmark, Belgium, Germany, Poland, Lithuania, Estonia and Finland. Study outcomes There are two co-primary effect variables: Funding The Scandinavian Candesartan Acute Stroke Trial receives basic funding from Norwegian health authorities. AstraZeneca supplies the trial drugs, and AstraZeneca and Takeda support the trial with limited, unrestricted grants. Summary The Scandinavian Candesartan Acute Stroke Trial is the first large trial of angiotensin receptor blockers in patients with elevated blood pressure and acute stroke, and aims to answer whether treatment with angiotensin receptor blockers is beneficial for this indication.