As the parties involved in talks on the future government of Northern Ireland take part in this week's key summit in Scotland, we take a look at the key issues and players.
Until the Stormont speaker Eileen Bell ruled his assembly alliance with the Ulster Unionists out of order last month, the PUP leader David Ervine might have expected to be attending the St Andrews talks as part of Sir Reg Empey's delegation.
But now - with the link broken - Mr Ervine will head his own delegation consisting of himself and three support staff.
The Progressive Unionists are strongly in favour of a return to devolution, not least because the UVF - the paramilitary group associated with the party - has made it clear that it wants a deal before it confirms any renunciation of violence.
David Ervine will head his own delegation
The UVF is suspicious of talk from London and Dublin about increased north-south cooperation if there's no deal - it argues that the loyalist ceasefire of 1994 was based on the assumption that the union was safe and authority would be channelled through a Belfast-based assembly.
So far the UVF has resisted pressure to disband or disarm and the latest Independent Monitoring Commission report found that the UVF leadership had sanctioned a murder bid on the alleged informer Mark Haddock.
That said, the Progressive Unionists have resumed contact with the Monitoring Commission which they broke off in late 2004 after it criticised the party for not using its influence to end UVF activity.
In 2005, the IMC recommended that thousands of pounds in Assembly grants be withheld from the PUP, but the Secretary of State, Peter Hain, continued to pay the cash because of what he called the "role that the PUP plays in attempting to secure peace and stability in the loyalist community".
The PUP is in favour of financial assistance for tackling deprivation in loyalist areas.
Last month, the PUP and Sinn Fein in Londonderry released a joint statement confirming they had "embarked upon a sustained dialogue to develop initiatives based upon common and agreed community issues".