Serena Williams claimed the WTA Championships title for the third time in her career with a 6-4 6-3 victory over Maria Sharapova.
The American triumphed in one hour and 29 minutes in Istanbul, taking her career record against the second-seeded Sharapova to 10-2 in the process.
The third seed's success rounds out a stellar 2012 that has included winning Wimbledon and the US Open, as well as striking gold at the London Olympics.
She has lost just once in 32 matches since her shock exit at the first round of the French Open in Paris, finishing the calendar year with seven titles to her name.
"It feels great to have achieved my dream," said Williams.
"The Turkish crowd were fantastic. I have never seen so many signs with my name on them before."
Williams broke her opponent's serve in the fifth game of the first set and comfortably held on to the advantage, allowing her to serve out for a 1-0 lead.
The 31-year-old then made a perfect start to the second, breaking immediately. Sharapova dropped serve for the third time to end the match, Williams rounding off proceedings with a rocketing forehand return.