Liz Truss has been crowned victor of the Conservative leadership contest and the country's next prime minister.
But what can we expect from what is certain to be a very busy week in Westminster?
Boris Johnson and new leader to meet the Queen
On Tuesday, both Boris Johnson and the new leader of the Conservative Party will travel to Balmoral to meet the Queen for the official handover.
The Queen will officially appoint the next prime minister shortly after seeing Mr Johnson.
Usually a new prime minister is invited to Buckingham Palace to be appointed by the Queen, but in a break from tradition this year, Her Majesty is staying in Scotland.
Downing Street speech
The new prime minister will then travel back from Balmoral to London before making their first speech in Downing Street as PM.
It is thought that Mr Johnson could make a farewell speech outside Number 10 on Tuesday morning before travelling up to Balmoral to see the Queen.
From Tuesday afternoon into the evening, it is expected that the new leader will begin to appoint their top government team.
This will include roles such as foreign secretary, chancellor, home secretary and business secretary.
The new prime minister is also likely to receive phone calls from other world leaders congratulating them on their appointment.
They may also make their first calls to their foreign counterparts. Ms Truss has said her first correspondence would be with Ukrainian President Volodymyr Zelenskyy.
First cabinet meeting
It is thought that the new prime minister could hold their first cabinet meeting having appointed their top team.
The main topic of conversation is likely to be the ongoing cost of living crisis, with the next leader of the country under growing pressure to intervene to ease the burden of spiralling energy costs as quickly as possible.
At midday, the new prime minister will take part in their first session of Prime Minister's Questions in the House of Commons - coming face-to-face with Labour leader Sir Keir Starmer.
Boris Johnson could watch on from the Conservative backbenches along with his predecessor Theresa May.
More ministerial appointments
During the remainder of Wednesday afternoon, it is expected that the new prime minister will continue to make ministerial appointments until all roles within the government departments are filled.
It is also likely that the PM will have more phone calls with their foreign counterparts.