Why was David Trimble not elected even though the majority of the NI Assembly supported him?
Under the Good Friday Agreement safeguards were put in place so both communities would feel they were adequately represented and their interests protected in the Northern Ireland Assembly. This meant that important votes, such as the appointment of a first minister, had to get support from both the unionist and nationalist communities, and the Good Friday Agreement specified that they should get a majority on both sides.
David Trimble and Mark Durkan both received a majority overall of the members of the assembly but Mr Trimble wasn't able to garner the support of a majority of the unionists present. He failed by one vote to beat that margin and that's why he couldn't be elected.
What does this defeat mean for his position as UUP leader?
At this stage it's hard to say. Obviously he would have preferred it if he had been voted in. I think there will be a period of introspection in the party, with those who are loyal to Mr Trimble saying that his policies have delivered in terms of IRA decommissioning and that the party should unite around him despite this rebuff. But there will be those sceptics who will say that Mr Trimble is part of the problem as well as his policies, and there may be others within the party who could provide a better lead.
What options does the UK Government have now?
The government is involved in talks with a number of parties who signed up to the Good Friday Agreement in the first place. It doesn't like any of the choices in front of it. The primary choices are to call fresh elections, which could damage the delicate political balance within the Northern Ireland Assembly, or to suspend the process, which will annoy some parties such as Sinn Fein.
However the government hopes the talks may point to a way forward, especially by involving the Alliance Party. It has long-standing complaints about the system by which the assembly is run, saying it institutionalises sectarianism in its voting patterns.
What would the parties like to see happen?
The Northern Ireland parties are as ever divided. The Democratic Unionists say that the government should now call fresh elections. They are hopeful that they will be able to improve their position, as they did in the recent Westminster elections. Sinn Fein also says it has nothing to fear by going to the people.
However the SDLP may well be nervous about losing their current position as the main nationalist party within the assembly. The UUP are thought to favour some kind of a suspension and an amendment to the current rules for voting in a first minister.
Would elections just lead to more deadlock in Northern Ireland?
Elections could complicate the current position. For instance, if Sinn Fein built on its recent gains in the Westminster elections it could become the main nationalist party and would therefore be in a position to provide a deputy first minister.
It's hard at this stage in the peace process to see an Ulster Unionist first minister and a Sinn Fein deputy first minister combining to form a workable administration.