The Stroke Foundation says it's possible to prevent 80% of strokes if doctors and the public follow a new set of guidelines to treat early symptoms.
The guidelines say Transient Ischaemic Attacks, or TIA, indicate that a full stroke is imminent and that immediate medical treatment is required.
A TIA can appear as weakness or loss of sight, speech, arm movement, or of facial muscles on one side of the body.
The Stroke Foundation says many people think they are safe after recovering from a TIA, but they are likely to suffer a full debilitating stroke.
Dr John Gommans, who wrote the guidelines, says four out of five strokes have been prevented by treating immediately those who present with early symptoms.