Theresa May is the longest serving Home Secretary in 50 years. She held the notoriously difficult position for six years, having been appointed in David Cameron's first coalition cabinet.
The current Prime Minister said that May will take over from him on Wednesday after he has taken his last PMQs and offered his resignation to the Queen.
Here is everything you need to know about the next prime minister, Theresa May.
Did she do a good job as Home Secretary?
The 59-year-old had mixed success in this role. Amongst others, her achievements include securing the deportation of radical Muslim preacher Abu Qatada after a lengthy legal battle.
However, under her charge, net migration reached record levels of around a third of a million, leaving the Government under intense pressure over its target of reducing the figure to below 100,000.
What's her stance on Brexit?
May's Brexit position was described as a "reluctant Remainer". Though she signed up to the Remain campaign, she kept a low profile during the lead-up to the vote.
Since then, May has caused controversy by saying she could not guarantee that EU citizens living in the UK would be allowed to stay after Brexit, insisting their fate must be part of negotiations with former EU partners.
How will she handle negotiations?
May has never been a character to hold back. Members of the Police Federation were stunned into silence when May attacked the organisation in a blistering speech earlier this year.
She's experienced in European politics too. Having begun her career at the Bank of England, May held posts such as Head of the European Affairs Unit and Senior Adviser on International Affairs.
Her no-nonsense approach seems to transcend across all areas of her life. Having revealed the "shock" of being diagnosed with Type 1 diabetes three years ago, she insisted that it "doesn't affect how I do the job. It's a case of head down and getting on with it."
What's her history in the Conservative Party?
The vicar's daughter started out with the Tories stuffing envelopes at her local Conservative Association.
From there she worked her way up, going on to be councillor in the London Borough of Merton between 1986 and 1994, during which time she also served as Chairman of Education and Deputy Group Leader and Housing Spokesman.
In 1997 she was appointed MP for Maidenhead, before becoming the first female chair of the Conservatives in 2002, and Home Secretary in 2010.
The famously private Tory lets little slip about her personal life.
During her appearance on BBC Radio 4´s Desert Island Discs, she told listeners her picks would include Abba's Dancing Queen and Walk Like A Man, from the musical Jersey Boys.
She also revealed the luxury item she'd take to the island would be a lifetime's subscription to Vogue. In a Thatcher-esque manner, she is famous for her love of kitten heels and designer outfits.
Theresa met her husband Philip John May whilst reading Geography at St Hugh's College, Oxford.
When asked about not being able to have children, she told the Mail On Sunday it's just "one of those things. You accept the hand that life deals you".