By Mark Devenport
BBC Northern Ireland political editor
It was one of the longest apprenticeships known to politics.
Peter Robinson had been, with one brief interruption, Ian Paisley's DUP deputy for 28 years.
Asked how he had coped with waiting so long for the party leadership, he quipped: "I am a patient man".
Peter Robinson has had a long apprenticeship
An estate agent by profession, Peter Robinson married Iris Collins in 1970 - the partnership later took on political as well as personal significance, when the two became a husband and wife team at Westminster.
He and his wife, Iris, who became Strangford MP in 2001, have three children.
Their partnership would come under an intense media spotlight nearly 40 years later.
In 1971, he was one of the founder members of the DUP.
The death of a school friend, Harry Beggs, killed that year in an IRA bombing at Northern Ireland Electricity headquarters, spurred the young Mr Robinson to enter politics.
He won the East Belfast parliamentary seat in 1979, turning over an Ulster Unionist majority of 17,000. He became DUP deputy leader a year later.
As deputy, he built a reputation as a canny strategist, plotting the DUP's election campaigns.
In the mid 1980s, he played a leading role in the joint unionist campaign against the Anglo Irish Agreement.
This led to the most controversial episodes in his career when he led 500 loyalists in an "incursion" into the Monaghan village of Clontibret.
He later plead guilty to unlawful assembly. Later that year, he was photographed wearing a beret at a rally of the paramilitary Ulster Resistance movement.
But alongside the protest politics, the East Belfast MP remained ready to chart a way forward.
He drew up a "Unionist Task Force" report together with Ulster Unionists Harold McCusker and Frank Millar.
In 1988, he participated in a meeting in the German city of Duisburg with other local parties at a stage when the formal political process remained frozen.
Together with the rest of the DUP, Peter Robinson opposed the 1998 Good Friday Agreement, honing in on aspects like the release of paramilitary prisoners.
Mr Robinson was Ian Paisley's deputy for 28 years
But he took office as minister for regional development, refusing to attend Stormont Executive meetings, but impressing his civil servants with his grasp of the detail of his brief.
He claimed credit, amongst other things, for introducing free travel for the elderly.
When the DUP became the main unionist party, Peter Robinson emerged as one of the party's most influential negotiators in the talks that led to the 2006 St Andrews Agreement.
He worked hard to limit the ability of ministers in a future executive to act as "independent warlords".
After the restoration of devolution in May 2007, he took the finance ministry and helped make revitalising the local economy the main theme of the new Stormont Executive's programme for government.
In his first budget, Mr Robinson froze the Stormont regional rate - a reminder that, as a stalwart of Castlereagh Council, he had long been a champion of keeping rates low and paring back on council expenditure.
In June 2008, Mr Robinson became the Northern Ireland first minister.
The challenges facing him then included when to complete devolution, by agreeing the transfer of policing and justice powers.
Given the disquiet amongst some DUP grassroots supporters over the "Chuckle Brothers" relationship between Ian Paisley and Martin McGuinness, Peter Robinson adopted a more detached relationship with the deputy first minister.
Peter Robinson's supporters view him as an effective manager - the kind of politician who will be able to cut down on waste in the public sector and boost the fortunes of local entrepreneurs.
His critics accuse him of being a "control freak".
Iris and Peter Robinson were married in 1970
He certainly is a politician you cross at your peril - when the SDLP minister Margaret Ritchie tried to cut funding to a UDA linked conflict transformation initiative she found herself on the receiving end of a withering attack from the finance minister who believed she had exceeded her legal powers.
In December 2009, Mr Robinson's wife Iris, announced she was stepping down from politics due to ill health.
It was the beginning of a series of revelations which came against the backdrop of intense negotiations over the devolution of policing and justice.
Mrs Robinson said she tried to kill herself while suffering depression after she had an affair.
Then in January 2010, Mr Robinson announced he was stepping aside temporarily after a BBC Spotlight programme said he did not report his wife's financial dealings to the authorities.
The BBC Spotlight programme reported that Mr Robinson's wife Iris obtained £50,000 from two developers for her teenage lover. It also reported that she broke the law by not declaring her financial interest in a public contract.
The programme also claimed that Mr Robinson had not reported his wife Iris' financial dealings to the relevant authorities despite being obliged by the ministerial code to act in the public interest at all times.
Mr Robinson issued a statement rejecting the allegations contained in the BBC's Spotlight investigation.
In February 2010, Mr Robinson resumed his role as NI first minister after receiving legal advice from a QC who said that, going on the information provided to him, he did not breach the code.
Then, in March, came the devolution of policing and justice powers to Northern Ireland after a vote in the Assembly.
Mr Robinson said on the day: "Throughout history there are times of challenge and defining moments. This is such a time. This is such a moment."