ARLENE Foster and Martin McGuinness were reappointed as First Minister and Deputy First Minister yesterday as the assembly met for the first time since last week's election.
The 108 MLAs who formally signed the membership roll included 29 newly-elected members.
Assembly members have two weeks before a new five-year programme for government must be agreed and an executive established.
The DUP and Sinn Féin remain the two largest parties following the election and enter coalition again amid a rise in paramilitary-style shootings and uncertainty over next month's EU referendum.
Mrs Foster told UTV: "I've always said it’s not easy, particularly with my background, working with Sinn Féin, however I believe it’s for the good of the people of Northern Ireland.
"It will be a business-like relationship and we will get on with doing the business."
Mr McGuinness said all MLAs have a "huge responsibility to take the Fresh Start Agreement forward; we have made a good start but there is more to be done".
“We are in a process of trying to put together a programme for government to continue to build on the progress we have already made," he said.
DUP MLA Robin Newton was elected as the new speaker, replacing Sinn Féin's Mitchel McLaughlin, who retired before the election.
Mr Newton said he aims to "uphold the standards that his predecessors have set".
Three deputy speakers were also elected - Sinn Féin's Caitríona Ruane, the SDLP's Patsy McGlone and the UUP's Danny Kennedy.
Ms Ruane was elected as 'principal deputy speaker', although the SDLP, Alliance and TUV refused to support the nomination.
Eamonn McCann and Gerry Carroll from People Before Profit are among the new intake of MLAs.
Mr Carroll wrote on his Facebook page that when they were asked to designate as "unionist, nationalist or other", he and Mr McCann wrote "socialist".
"We will be put in the 'other' camp, but we are clear where we stand," he said.
"This isn't the Alliance Party. This is the new socialist alternative."
MLAs also undertook to support the rule of law, challenge paramilitary activity and accept no authority but a democratic mandate.
The DUP last week retained the 38 seats it held in the last assembly, while Sinn Féin lost one to finish with 28.
The Ulster Unionists have 16 seats, while the SDLP now has 12. Alliance has eight MLAs, and the Greens have doubled their representation to two.
