Swimming at the 2007 World Aquatics Championships – Women's 400 metre individual medley
The Women's 400m Individual Medley (IM) at the 2007 World Aquatics Championships took place on 1 April (prelims & finals) at the Rod Laver Arena in Melbourne, Australia. As the event was over 200 meters in length, no semifinals were held in it and the top 8 swimmers from the preliminary heats advance directly to the single final heat. 40 swimmers were entered in the event, of which 48 swam. Existing records at the start of the event were: Swimming at the 2007 World Aquatics Championships