A "rainbow" coalition - how might it work?
Policy priorities would need to be agreed by the parties
Plaid Cymru, the Conservatives and the Liberal Democrats would draw up an agreed programme of policies based on the manifesto commitments they made to voters during the Welsh assembly election.
They would also agree to share out the seats around the cabinet table amongst each of the three parties - so they all have a say in the day-to-day decisions involved in running an administration.
Also crucial would be to agree processes for those decisions.
It is one thing to agree on a set of policy priorities and quite another to respond quickly to events in a way all three parties are happy with.
Who would hold the upper hand?
Plaid Cymru has 15 seats in the new assembly, the Conservatives 12 and Liberal Democrats 6.
As the biggest party Plaid would be senior partner but in order for any coalition deal to be agreed all three parties would need to be confident that they would have a fair influence on the assembly government's policies.
Who is likely to be the first minister if this can be agreed?
As the leader of the largest party Plaid Cymru leader Ieuan Wyn Jones would reasonably expect to be first minister.
Senior cabinet positions would be offered to the Conservatives and Liberal Democrats to balance things.
There could be, for example, be two deputy first ministers - one Tory and one Lib Dem
Is there enough common ground between Plaid and the Tories to have a workable government?
In terms of policies there probably is.
More difficult is the way some of the parties' supporters and potential future voters might feel about working with the other party.
Some Tories would argue against supporting a nationalist party committed to the eventual break-up of the UK.
Plenty of Plaid Cymru supporters would have difficulty putting the traditional enemies of the left, the Conservatives, back into power in Wales.
A Labour opposition would make much of Plaid and the Lib Dems giving the party of Margaret Thatcher and former Welsh Secretary John Redwood seats in a Welsh government.
Will all AMs be happy with this?
Obviously Labour AMs who had expected to be in government might be a bit miffed.
There will be some amongst the other three parties uneasy with joining-up with parties who will be their main challengers in their local patches at future local, UK and Welsh elections.
It is not so easy to argue in an election campaign that another party would be disaster in power if your party is working with that rival in government in Cardiff Bay.
The clock is ticking, so how long is this process going to take before we really have a deal?
Not long. A new first minister must be chosen by 30 May at the latest, to avoid another election
Plaid Cymru and the Liberal Democrats have special conferences on 26 May to sanction any deal and the Conservatives are expected to agree or reject in principle a deal before then.
We should know whether it is going to happen or not in just over a week.
Why doesn't the Lib-Lab coalition seem to have come off?
There was strong opposition from Liberal Democrats across Wales to going into coalition with Labour.
Lib Dems running local councils in Cardiff, Bridgend, Swansea and Wrexham were particularly opposed to a deal with their main opponent in next year's local elections.
An unnamed Labour assembly source who suggested a coalition with the Lib Dems would allow Labour to "hug them close and strangle them slowly" probably didn't help either.
The comment fed fears amongst some Lib Dems that Labour could not be trusted.
Labour is still the largest party - how would it cope if it was in opposition?
While Labour is used to being in government it has known since the election that the mathematics in the assembly chamber now make a "rainbow coalition" possible.
Plaid, the Tories and Lib Dems have been talking about it for years but Labour falling from 29 seats to 26 has made it feasible.
With the other three parties in government, Labour's new role would be to scrutinise the new administration.
Should the three party government prove to be unstable Labour might reap the rewards in future elections
Does Labour still have a chance of forming a government?
It does - if the three parties fail to make progress in talks over the next few days the Lib Dems could return to Labour.
Labour leader Rhodri Morgan has said he is "keeping the door open".
Plaid Cymru are also still considering the possibility of supporting a minority Labour administration, in exchange for concessions on policy - a so called "stability pact".
What would happen to Rhodri Morgan if Ieuan Wyn Jones became first minister?
He would become leader of the opposition.
He would then decide whether to stay in that role for some time, to help Labour adjust to its new role, or retire as leader to give someone new a four year run up to the next assembly election.
Mr Morgan said he would step down as first minister after two years anyway so would not be expected to remain Welsh Labour leader beyond 2009.
And how would this go down in Westminster and with Gordon Brown - after what's happened already with the SNP in Scotland?
Like a lead balloon.
Labour has lost control of Scotland to nationalists, now it would be losing Wales to nationalists and Tories.
We could expect greater tension between the Welsh and Scottish first ministers and the new man with the keys to 10 Downing Street.