Four-time defending champion Roger Federer was seeded number one for Wimbledon on Wednesday, with Justine Henin getting the top spot for the women.
Rafael Nadal, last year's runner-up, was seeded number two ahead of Andy Roddick. Defending women's champion Amelie Mauresmo was seeded number four in line with her world ranking.
Wimbledon, the third Grand Slam tournament of the year, begins on Monday. The draw will be held on Friday.
In determining the seedings, Wimbledon took past performances on grass into account. The seedings at other Grand Slams mirror the rankings.
The top 18 women are seeded according to their WTA ranking, with French Open champion Henin number one in her attempt to improve upon her performance as losing Wimbledon finalist in 2001 and 2006.
Maria Sharapova, who won the 2004 title at age 17, is seeded number two, followed by Jelena Jankovic. Two-time winner and Australian Open champion Serena Williams is number seven.
Below the top three men, there were mostly minor movements against the rankings. Fifth-ranked Novak Djokovic was moved up to the number four seeding after winning in Estoril, Miami and Adelaide.
Eleventh-ranked Tomas Berdych was seeded number seven, switching places with Tommy Robredo, while Marcos Baghdatis was the biggest beneficiary of the system. The Cypriot player, who lost to Nadal in straight sets in last year's semifinals, was seeded at number 10, six places above his ATP ranking.