Foster carried the flag at the World Short Course Championships in April
Swimmer Mark Foster has been chosen to carry the Olympic flag for Britain at the opening ceremony on Friday.
The 38-year-old from Essex - competing in the 50m freestyle - was chosen from a poll of all the British competitors.
"It means the world, it's a real privilege, it's a real honour," Foster told BBC Sport ahead of competing in his fifth Games.
Foster, who won silver at the 2008 world short course championships, will be looking to add to his 47 medals.
He added: "I put my name forward. I suppose in my heart of hearts, I didn't believe that I'd actually get nominated and actually get to carry the flag.
"It is a fantastic honour when people in the past like Matthew Pinsent, Steven Redgrave, Kate Howey, a lot of wonderful people have carried it before. I'm really, really chuffed."
Howey was the British flag-bearer at Athens in 2004, with Pinsent in Sydney 2000 and Redgrave getting the nod in Atlanta 1996.
The veteran is the first swimmer to carry the British flag at the Olympics since 1964, when Anita Lonsbrough won gold in the 200m breaststroke in Rome.
Foster, who swims for the University of Bath, broke the British record in the 50m freestyle in June and said winning a medal in Beijing would be the highlight of his career.
The British Olympic Association appointed Foster the flag bearer after asking each sport represented in Team GB to nominate one candidate. The team leaders of each sport then voted on the shortlist.