Theresa May is the new Prime Minister of the United Kingdom.
She becomes the second woman in UK history to take the top job.
The 59-year-old politician will take over from David Cameron, who announced he was stepping down following the decision by the Uk to leave the EU.
Mrs May, who backed staying in the EU, has been home secretary since 2010. She is the MP for the area of Maidenhead in the south east of England.
The Home Secretary is a big job in the government. It means she is in charge of things like police, keeping the country safe and immigration.
Theresa started in politics by stuffing envelopes at her local Conservative club.
Mrs May will become the second female prime minister after after Margaret Thatcher, who held the top job from 1979 to 1990.