The swimming competition at the 12th FINA World Aquatics Championships was held in Rod Laver Arena in Melbourne, Australia, from 25 March to 1 April 2007.
This portion of the 2007 Worlds featured 40 events (20 for males, 20 for females), all swum in a long course (50 m) pool: The 2007 World Championships served in qualifying for the Swimming portion at the 2008 Olympics in two ways: 166 nations had 1,142 swimmers entered at the 2007 Worlds:[1] Morning/heats sessions began at 10:00 a.m., with the evening sessions (semifinals and finals) beginning at 7:00 p.m. All events were contested in a long-course (50 m) pool.
For the individual 800 m and 1500 m free events, heats were held in the morning with finals in the next day's evening session (approximately 36 hours apart).
Key * Host nation (Australia)On 11 September 2007, an anti-doping ban was issued to Tunisia's Oussama Mellouli, with a retroactive nullification of his results which included his swims at the 2007 Worlds.
Mellouli had finished in the top-3 in 2 events, and consequently, his results nullification adjusted the overall medals standings, particularly effecting Australia, Italy, Poland, Russia and Tunisia (Tunisia was removed all together, as Mellouli was the country's only medal winner).