Iain Duncan Smith knows all about rebellion against the party leadership, having been at the heart of it so many times himself.
Duncan Smith won party leadership in 2001
He was often at the centre of the parliamentary Euro-troubles that seriously destabilised John Major's government, helping to orchestrate vote after vote against his own side on the Maastricht Bill in 1992 and 1993.
Nevertheless he defied conventional political wisdom in September 2001 to become the Tory Party's eighth leader since Winston Churchill, fighting off heavyweights Ken Clarke and Michael Portillo to claim the crown after the Conservatives' second landslide general election defeat.
But Mr Duncan Smith's history puts him in a weak position when it comes to issuing demands for loyalty.
Since becoming Tory leader, the former Scots Guardsman has faced near constant speculation about his future amid talk of plots and reported disquiet with his leadership.
A frontbench spokesman, Crispin Blunt, even quit his post on local election night earlier this year to voice his concern - an evening which saw the Tories make significant gains on Labour.
And despite the backstage whispers, as another conference season arrives, Mr Duncan Smith is still in place. Last year he warned his doubters not to underestimate "the quiet man", warning his detractors that he would not shirk in his mission to transform his party.
Mr Duncan Smith rose to the top incredibly quickly, having been first elected in 1992 and unlike his equally prodigious predecessor, having no experience of government.
DUNCAN SMITH'S CV
Born April 1954
Joined Tory Party in 1981
Contested Bradford West 1987
Elected as MP for Chingford 1992
Social security shadow 1997-99
Defence shadow 1999-2001
Party leader 2001-
Indeed, he was notable in his first Parliament for his disloyalty as one of the few new MPs to join the Maastricht rebellions.
Support from Thatcher
A former army officer, who saw active service in Northern Ireland, he was a shadow defence secretary under William Hague.
He is generally seen as an admirer of US society and has extensive contacts among Republican politicians and the defence establishment.
An active Christian, Mr Duncan Smith joined the Tory party in 1981, after being profoundly affected by Lady Thatcher's election victory in 1979.
He is said to be close to the former prime minister, who was reported to be an unofficial backer of his campaign.
Lady Thatcher is believed to have been behind a propaganda coup which saw Mr Duncan Smith hold a meeting with George W Bush's defence secretary, Donald Rumsfeld, before his UK opposite number Geoff Hoon had a chance to brief him on EU proposals for a rapid reaction force.
Father of four
He is fiercely opposed to any moves towards a potential European army and that he believes the UK should back American plans for a National Missile Defence system.
In the 1997 battle for the Tory leadership Mr Duncan Smith not only rejected William Hague to back leading Eurosceptic John Redwood, but he ran his campaign.
Only after Mr Redwood was knocked out of the contest did Mr Duncan Smith swing behind the eventual winner.
As social security spokesman he led Tory opposition to major planks of the government's programme such as welfare to work.
He is married with four children; his wife Elizabeth is a secretary.
His father was a World War II pilot before he went into business; his mother was a ballet dancer.