The women's 200 m butterfly at the 2009 World Championships took place on 29 July (heats and semifinals) and on the evening of 30 July (finals) at the Foro Italico in Rome, Italy.
Records
The existing records at the start of the event were:
References
Swimming at the 2009 World Aquatics Championships – Women's 200 metre butterfly Wikipedia(Text) CC BY-SA