Roger Federer and Justine Henin have been named the 2007 world champions by the International Tennis Federation.
Federer and Henin dominated the tennis world in 2007
Both are ranked number one in the world and ended the year with wins at the season-ending championships.
Federer, who also won the Australian Open, Wimbledon and US Open titles to bring his Grand Slam haul to 12, took the award for the fourth year running.
Henin, who won the French and US Open titles, was named world champion for the third time.
Federer, 26, said: "It is an honour to be named ITF world champion for the fourth year running.
"Each year brings new challenges, and I am proud that I have been able to raise the level of my game when needed.
"It gives me great satisfaction to have won another three Grand Slam titles and maintained the number one ranking."
Henin, 25, becomes women's world champion for the second year running, having also received the honour in 2003.
The Belgian said: "This has definitely been the best season of my career so far and I still think my best tennis is yet to come."
American twins Bob and Mike Bryan and the Zimbabwe-US pairing of Cara Black and Liezel Huber are the 2007 doubles world champions.
Ricardas Berankis of Lithuania and Urszula Radwanska of Poland are the junior world champions.