More people die from strokes each year in Ireland than from breast cancer, prostate cancer and bowel cancer combined.
The Irish Heart Foundation is setting up more than 250 awareness campaigns this month, teaching people how to spot the warning signs.
They're using the acronym FAST which stands for Face, Arms, Speech and Time - the things we're supposed to check before quickly dialling 999.
Each year, around 2,000 Irish people die from strokes, but doctors believe information campaigns can help.
"Nobody thinks that these things can happen to them until it does, said Doctor Sinead Beirne
"When someone's chatting to someone and their speech is going funny … they don't think 'stroke'. At least there's this awareness now."
She said ignoring the signs to "wait and see" can result in a few days' of vital tissue damage.