Why does the winner of the Masters Golf Tournament get the 'Green Jacket'?

It is a tradition of the Masters Golf Tournament since 1949. The green coat is the official attire of the Augusta National Golf Club. When players win the Masters they become members of the exclusive club for a lifetime.

For a year after winning the Masters the champion keeps the jacket. After that they return it to the club where it stays until they return to play.

The winner of the tournament in the previous year puts the jacket on the new winner by tradition.