Profile: Malcolm Turnbull
Australia's Minister for Communications Malcolm Turnbull is set to become Australia's next leader after successfully challenging the leadership of Prime Minister Tony Abbott.
Mr Turnbull is known as a competent minister and confident communicator who is well-liked across the political divide, polls have shown.
The Liberal Party is conservative, but the communications minister is known for his progressive views, notably his support for climate change action and gay marriage.
Those views are unpopular among the more right-wing members of the party, and some are unconvinced that Mr Turnbull will stick to core party policies.
The question of internal support has become more crucial in recent months. Amid plummeting support for Prime Minister Tony Abbott, Mr Turnbull had been touted as a strong contender to replace him.
Polls conducted by research company Ipsos Australia, including the latest done in August 2015, had consistently found him to be the most preferred person to be the Liberal leader and prime minister, over Mr Abbott and Foreign Minister Julie Bishop.
In February, Mr Turnbull was widely expected to challenge the leadership, but the Liberal party voted not to open up Mr Abbott's position to challengers.
Lawyer and businessman
A successful former lawyer and businessman, Mr Turnbull is now one of the richest politicians in Australia, having made the Business Review Weekly Rich 200 List several times.
Raised by a single parent, he grew up in the Vaucluse and Double Bay neighbourhoods of Sydney.
He attended a state school as a child and later received a scholarship to attend a private high school. After studying law at the University of Sydney, he won a Rhodes scholarship to further his studies at Oxford University.
Mr Turnbull briefly worked as a journalist for several outlets, including The Sunday Times in the UK, before embarking on his law career.
One of his biggest achievements was defending former British spy Peter Wright in the "Spycatcher" case in the 1980s. Mr Wright wrote a memoir about his time in MI5, and the British government sought to ban its publication in the UK. Mr Turnbull successfully overturned the ban.
He went into the technology business in the 1990s, and co-founded one of the biggest Australian internet service providers at that time, OzEmail.
In 2004, Mr Turnbull was elected as the MP for Wentworth, the electoral seat where he grew up and where he continues to live with his wife Lucy Hughes, who was the first female Lord Mayor of Sydney.
He quickly rose through the parliamentary and party ranks, serving on various committees. He was briefly the environment and water resources minister in John Howard's government before his party's coalition lost to Labor in the 2007 federal election.
He was elected as leader of the opposition in 2008, but a year later faced two leadership challenges, losing the second one narrowly to Mr Abbott by just a single vote.
Mr Turnbull's downfall was attributed to his views on climate change and support for an emissions trading scheme.
However, his credibility was also severely damaged when he attacked then-PM Kevin Rudd over an email purportedly showing corruption, but which was later found to have been faked by a top civil servant. The so-called "OzCar" affair damaged his standing with his colleagues and the public.
'Not greatly loved by party'
In his current role as the communications minister, Mr Turnbull earned plaudits for doing his job well and having a good grasp of public policy. He is also known as a skilled orator and debater.
Dr Peter John Chen, a politics lecturer at the University of Sydney, says: "He has the hallmarks of an effective leader... But he is not greatly loved by his party, because he tends to be on the left while his party is moving towards the right."
Mr Turnbull is also known for his tendency to be abrasive with colleagues; he has for instance previously publicly blasted Mr Abbott's climate change plan.
Mr Turnbull has also been criticised for failing to consult with his colleagues before announcing his position on issues, such as his support for an apology to Australia's indigenous "Stolen Generation".
Dr Sally Young, associate professor of politics at the University of Melbourne, says Mr Turnbull is "more of his own man", describing him as "less intimidated" by powerful media baron Rupert Murdoch.