It is estimated that more than 56,000 strokes will be experienced by Australians this year (new and recurrent) and that half of Australians are living with the effects of a stroke which remains the third leading cause of death in Australia and kills more women than breast cancer and more men than prostate cancer. As more than 80% of strokes may be prevented and four in 10 stroke survivors have a recurrent stroke within a decade it is very important we understand the aetiology of strokes and how we may intervene effectively to reduce incidence and morbidity.