A new campaign by the NHS in England is encouraging people who experience the first sign of a stroke not to delay calling 999, after analysis of calls made in the last year showed the average time to do so was nearly an hour and a half.
England's most senior doctor says stroke symptoms might not appear obvious or dramatic, but they are always a reason to act quickly.
About 100,000 people have a stroke each year in the UK and more than a third die from related issues, making it the fourth biggest cause of death in the UK.
The most common symptoms are struggling to smile or raise an arm, and slurring words when speaking.