We'll find out by this evening whether or not there will be a new government.
Votes will be counted from the members of Fine Gael, Fianna Fáil and the Green Party on whether or not they support the programme for government.
It's 139 days since the general election, almost double the length of time it took to form the last government.
Counting of the postal votes will begin around lunchtime with the results expected sometime this evening.
Fine Gael has the easiest job with just around 700 votes to count from their electoral college system.
Fianna Fáil will have the most, with more than 14,000 individual members eligible to vote.
But it's expected both of those parties will approve the deal, and they only need 50 per cent plus one vote.
The Green Party's count will be subject to the most attention today.
They need two thirds of members to back the deal, and there's been a vocal campaign against it.
Sources in the party believe they do have the numbers, but it's expected to be tight.
If there's three yes votes then Micheál Martin will be elected Taoiseach tomorrow.
If not, it's back to the drawing board.