Malcolm Turnbull has been elected as leader of the Australian Liberal Party 54-44, unseating Prime Minister Tony Abbott after a leadership spill.
With this victory, Mr Turnbull will now be Australia's fifth Prime Minister in eight years. Julie Bishop retained her position as deputy leader with a 70-30 victory over Kevin Andrews.
Mr Abbott was earlier confident that he would remain as Prime Minister ahead of the vote.
Earlier this evening, Communications Minister Malcolm Turnbull stepped down from Cabinet to take on Mr Abbott – a move which had divided his party, and his country.
"The Prime Minister has not been capable of providing the economic leadership our nation needs," Mr Turnbull said. "He has not been capable of providing the economic confidence that business needs.
"Now we are living as Australians in the most exciting time. The big economic changes that we're living through around here and around the world offer enormous challenges and enormous opportunities, and we need a different style of leadership."
One of those backing the minister's move was Liberal backbencher Wyatt Roy.
"We do have to achieve very significant reform for this country," Mr Roy said. "We need to be more productive, more innovative, more entrepreneurial, and if you're going to achieve that there are some harsh realities that I think we've learned in recent history. You need a lot of political capital and I think that you need a process that you explain things."
But Mr Abbott hit back, saying the Liberal party is better than this and that it is up to the Australian people to elect its Prime Minister.
"The prime ministership of this country is not a prize or a play thing to be demanded," Mr Abbott said. "It should be something which is earned by a vote of the Australia people."
A leadership spill had been on the cards since February, but Mr Turnbull declined to challenge. At the time Mr Abbott asked MPs to give him six months to turn things around.
The polls show that that hadn't happened.
"Regrettably, there are few occasions that are entirely ideal for tough calls and tough decisions like this," Mr Turnbull said.
The move had angered many, who are sick of a revolving door of leaders.
Late this evening Mr Abbott was quick to move, announcing a vote for later tonight to catch Mr Turnbull's supporters on the hop.