By Mark Devenport
BBC Northern Ireland political editor
Peter Robinson has had a long apprenticeship
It has been one of the longest apprenticeships known to politics.
Peter Robinson has been, with one brief interruption, Ian Paisley's deputy for 28 years.
Asked how he had coped with waiting so long for the party leadership, he quipped: "I am a patient man".
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.
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.
Mr Robinson was Ian Paisley's deputy for 28 years
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.
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.
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".
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.
Away from politics, Peter Robinson relaxes by breeding Japanese Koi carp. He collects an array of ties, and enjoys golf and bowling. He and his wife, Iris, who became Strangford MP in 2001, have three children.
The challenges facing the future first minister include 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 is expected to adopt a more detached relationship with the deputy first minister.
At the same time, he will want to convince voters and potential investors that the Stormont executive can deliver good government.
So expect a cooler style, but not necessarily any breakdown in communications.