The Rev Ian Paisley and Martin McGuinness today mark the end of almost four decades of bitter and bloody conflict in Northern Ireland when they are formally appointed first minister and deputy first minister.
Taoiseach Bertie Ahern and British prime minister Tony Blair will be in the visitors' gallery of Parliament Buildings, Stormont this morning to witness the creation of a powersharing government led by political polar opposites the Democratic Unionist Party and Sinn Féin.
This will be the first time that Northern Ireland will be run by a government in which all the main nationalist and unionist parties have agreed to operate power together.
In the Assembly, unionist Dr Paisley and republican Mr McGuinness will affirm their pledges of office, which includes support for the PSNI and the courts, as will the 10 executive ministers.
Unlike the first executive that followed from the 1998 Belfast Agreement collective cabinet responsibility will apply in this government. In the first executive, DUP ministers functioned virtually autonomously and refused to sit in the executive with Sinn Féin ministers.
In contrast on this occasion both Dr Paisley and Mr McGuinness have agreed a busy programme of work for the days and weeks ahead.
After the Assembly formalities are concluded this morning Mr Ahern and Mr Blair will join the first minister and deputy first Minister for tea in Dr Paisley's office. There will then follow a reception in the grand hall of Parliament Buildings at which Dr Paisley, Mr McGuinness, Mr Blair and Mr Ahern will speak.
There has been unprecedented interest in today's installation of the new government, according to Stormont officials, with accreditation provided for more journalists than during the lead-up to the Belfast Agreement or for George Best's funeral.
In addition to the Taoiseach and British prime minister, there will be several dignitaries attending including US senator Edward Kennedy, asked by the White House to represent President George Bush.
The various religious, business and civic sectors of society will also be represented. There will be a particular agreed focus on victims' groups - more than 3,700 people died since the modern troubles began in 1969.
The positive build-up to today's events was slightly soured, however, by a complaint by former deputy first minister Séamus Mallon that he did not receive an invitation from the Office of First Minister and Deputy First Minister.
Each of the parties was allotted a certain number of places and while the SDLP offered Mr Mallon an invitation from its allocation, he said, "I don't regard that as an invitation."
An Ulster Unionist Party spokesman also said former first minister David Trimble did not receive a personal invitation but that in any case he could not attend.
Mr Ahern and Tánaiste Michael McDowell are due to fly to Belfast on the Government jet. Former PD minister of state Liz O'Donnell said she expected they would talk about the Taoiseach's finances in the margins of events at Stormont.