9/11: Survivors recall escapes from the WTC attacks
10 September 2011 Last updated at 20:03 BST
The BBC's Steven Evans was on his way to a meeting in the top floor restaurant in the World Trade Center's south tower when the first plane struck.
He decided to get a coffee before he went up - a decision that saved his life.
On the 10th anniversary of the attacks, he returned to the site of the World Trade Center where he met two other people who had lucky escapes.