The talks have been going on all year. Now, after ten months of negotiations, agreement on the rules of a Scottish independence referendum is thought to be near. Officials are putting together a draft package to be rubber-stamped by the two sides. But what's in it? Here's an update on what we know about the state of play.
The biggest issues being discussed are the timing of the referendum and the question to be asked. The British government had kicked over a fuss on the SNP's preferred autumn 2014 date (Alex Salmond's party having originally pledged in its 2011 election manifesto not to hold a referendum until the second half of the current Holyrood parliament). But it is thought to have conceded that date fairly early on in the negotiation process. Apart from anything else, it will take another 12 months or so for the primary legislation required in both Holyrood and Westminster to work their way through both parliaments. These things take time, so London is likely to accept that its initial optimistic 18-month guess - for a referendum by mid-2013 - has long ago become unrealistic.
The other big sticking point is over the nature of the question to be eventually put to Scottish voters. Both sides are thought to be prepared to accept giving the Electoral Commission the job of vetting this. It looks like London will get its way over the number of options presented: 'yes' and 'no' will be all there is on offer. The third 'devo-max' term, which polling suggests would do the best of all, won't even appear on the ballot.
All this serves to place some SNP distancing from the devo-max idea in context. One of the party's MPs I've spoken to recently was keen to point out that, as the SNP's policy position was independence or bust, it was up to 'civil Scotland' to try to coalesce around a third devo-max option. Nothing to do with the SNP, you understand - so the failure to come up with a cohesive set of ideas is the fault of 'civil Scotland' and not the nationalists. The MP pointed out that the unionists south of the border are also split on the terms of any future devolution - conveniently demonstrating the difficulties of coming to any kind of agreement on where to go next after Scotland votes 'no'.
That result is not guaranteed, of course, but if the polls remain the same that will be the outcome. This explains why the Scottish government is so keen to extend the franchise to 16- and 17-year-olds. It might seem like a blatant manipulation of the process, but the SNP will take any votes they can get. The UK government, keen to secure agreement on a binding set of terms, is likely to make a concession here - confident that the bigger picture looks good (and that young voters are notoriously poor at actually bothering to vote).
It's taken a ridiculously long time to get this far. But the two governments do appear to have adopted a pragmatic line rather than going down the route of all-out war via the courts. The constitutional crisis we feared in January has been replaced by some plain, straightforward horse-trading. Now we just need to find out what the exact terms are - and then work out who's won the battle for the rules of the game.