Stroke is a clinical syndrome.(1) In the investigation of stroke and transient ischaemic attack (TIA) imaging is used to differentiate: vascular from non-vascular lesions, such as tumours or infections ischaemic from haemorrhagic stroke arterial from venous infarction and to distinguish anterior and posterior circulation strokes to determine whether a tight carotid stenosis is symptomatic or not. In the future imaging may be used to show the extent of salvageable tissue in acute stroke before treatment. Imaging should be used to direct management. Investigation should be organised to resolve specific, preferably articulated, management dilemmas. This may include imaging to clarify and guide prognosis.