World number ones Roger Federer and Justine Henin were named 2007 ITF World Champions, the governing body announced on Monday.
Federer, who won eight titles during the season, became only the second player after Pete Sampras to receive the accolade for the fourth successive year.
The 26-year-old reached all four major finals for the second successive year, winning the Australian Open, Wimbledon and US Open. He also became the first player to earn over $10 million in annual prize money.
"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," said Federer.
The 25-year-old Henin, who triumphed at Roland Garros and the US Open, captured a career-best 10 titles in 2007.
With an impressive 63-4 win-loss record, she became the first woman to earn more than $5 million in a single year.
"This has definitely been the best season of my career so far and I am delighted to be named ITF world champion once again," said the Belgian, who missed the Australian Open in January following the breakdown of her marriage.
"It has been a very challenging year overall, but I have stayed positive and proved that nothing is impossible if you work hard. I still think my best tennis is yet to come."
American brothers Bob and Mike Bryan, and Cara Black and Liezel Huber were named doubles world champions.