Who is Stephen Crabb?
Appointed amid the furore of Iain Duncan Smith's explosive resignation, Stephen Crabb has already been tipped to make the headlines in his own right.
The 43-year-old former Welsh secretary, raised by his mother on a council estate in Haverfordwest, has a back story that contrasts sharply with that of many of his cabinet colleagues.
He has spoken in interviews of the "horrible decisions about what food and clothing was affordable" as he was growing up.
Many see his personal story as well suited to his new role at the Department for Work and Pensions, where he will take on the reforms championed by Mr Duncan Smith and fiercely opposed by some charities and opposition MPs.
Stephen Crabb MP
- 43 years old
- MP for Preseli Pembrokeshire since 2005
- Promoted to Welsh secretary in July 2014 having been a minister in the Wales Office
- Was previously a government whip
- Has worked for the National Council for Voluntary Youth Services and the London Chamber of Commerce and Industry
- Keen rugby player and has run the London Marathon three times
In an interview with BBC Wales Westminster correspondent David Cornock last month, the MP for Preseli Pembrokeshire described how the welfare system had provided a "genuine safety net at a time of crisis" for his family.
"I had a mother who, as we got older, moved progressively from a position of complete welfare dependency to being fully economically independent, working full-time," he said.
"And that has to be the model of the way the welfare system should work."
Mr Crabb says his first political memory is the 1979 general election that brought Margaret Thatcher to power, and that witnessing her flagship right-to-buy policy on his street had a "huge impact" on him growing up.
After attending Tasker Milward school in Haverfordwest, he studied at Bristol University, gaining a first-class degree in politics, joining the Conservative Party after graduating.
He won his seat at the second attempt in 2005, and worked as a whip before becoming a minister in the Wales Office, where he was appointed secretary of state in July 2014.
Mr Crabb, who is married with two children, lives near Haverfordwest and is a keen rugby player.
He is the first Conservative cabinet minister for a century to have a beard - and David Cameron recently jokingly suggested he could be the next James Bond after comparing him to Hollywood star Russell Crowe.
It's not the only role the new work and pensions secretary - who unlike Mr Duncan Smith supports the UK remaining in the European Union - has been tipped for.
He is well thought-of in Conservative circles - and with David Cameron to stand down as party leader before the next election, some think he could be in line for a bigger promotion.
Scottish Conservative leader Ruth Davidson recently told the Daily Telegraph she would "find it very hard to vote for anyone else" if he was involved in a leadership contest, while the influential Conservative Home website says his promotion will boost his leadership prospects.
"His political convictions were not forged on the playing fields of Eton and his summer job was working on a building site," WalesOnline's political editor David Williamson wrote last week, in an article asking whether Mr Crabb could be the man to unite the Tories after the EU referendum.
Asked about leadership ambitions by the BBC's David Cornock, Mr Crabb said: "I don't think I have an ambition to become leader, really.
"It doesn't feel that long ago in my life that the thought of becoming an MP seemed outlandish and unrealistic, so to find myself a few years ahead sitting at the cabinet table doing a job for Wales, I just feel incredibly blessed with that really."
He went on to say he would fancy "a shot at doing something UK-wide" in the future.
On the morning of his appointment, he tweeted about his "busy Saturday" including an advice surgery in Haverfordwest followed by Wales versus Italy in the Six Nations rugby.
With his sudden elevation into one of the most high-profile jobs in cabinet, it has just got even busier.