The NatWest Women's T20 Quadrangular Series was a women's Twenty20 International series which took place in England in 2011. The top four ranked teams in the world competed: Australia, England, India and New Zealand. The tournament consisted of a round-robin group stage, in which England and Australia finished as the top two, and then a third-place play-off and a final were contested to decide the final positions. England defeated Australia by 16 runs in the final. The tournament was followed by an ODI Quadrangular Series, with the same teams competing.