What you need to know about the latest NI powersharing talks

So what is preventing a return to devolved government and is there any reason to believe this process will succeed where so many other initiatives have failed?

- Stormont collapsed three years ago this month. Why?

Few could ever have predicted that the issue to pull down Stormont's peace process structures would be a row about a botched green energy scheme. But so it came to pass in January 2017 when Sinn Fein withdrew from the mandatory coalition administration it jointly led with the DUP.

The republican party had demanded that DUP leader and then first minister Arlene Foster step down temporarily to facilitate an investigation into her handling of the ill-fated Renewable Heat Incentive (RHI) scheme. When she refused, the late Sinn Fein deputy first minister Martin McGuinness resigned - a move that pulled down the executive.

The row over the RHI scheme destroyed relations between the parties, sparking a range of further disputes over traditional issues that had previously not posed an existential threat to the institutions.

A wrangle over proposed legislation for Irish language speakers and the region's ban on same-sex marriage soon emerged as key roadblocks. Ironically, the bust-up over RHI soon faded into the background and, even though a public inquiry report on the scheme is due, it is no longer one of the issues considered pivotal to restoration.

- Has the general election changed things?

The DUP and Sinn Fein both had very disappointing elections. The DUP lost two of its 10 Westminster seats and saw its vote drop significantly. Sinn Fein still has seven parliamentary seats, but its vote fell by a quarter on the last election and the party suffered an extremely embarrassing defeat in Foyle, where the SDLP trounced its incumbent MP with a 17,000 majority.

For many, the outcome was the public passing judgment on the two largest parties' failure to restore powersharing. The election also provided further evidence of a shift towards more centre-ground politics in Northern Ireland - a trend borne out by another positive showing for the cross-community Alliance Party. The results undoubtedly created a fresh impetus for the big two to get Stormont back up and running.

-What about the DUP and the Tories?

The sight of Northern Ireland Secretary Julian Smith blaming the DUP for the failure to secure a pre-Christmas deal served as a powerful reminder that confidence and supply is a thing of the past. That Westminster arrangement had been the elephant in the room during previous talks initiatives, with the other Stormont parties accusing the Government of dancing to the DUP tune and undermining its stated independence in the region.

The general election appears to have changed this dynamic. The other parties seem content with Mr Smith's handling of the process, thus far, and the DUP knows it can no longer rely on the Government for political cover.

- Are there other factors at play that make this process different?

The powersharing impasse created a slow-burning crisis in Northern Ireland's public services. With no elected ministers, and the Government reluctant to reintroduce direct rule, civil servants have been left to run departments in a strange governance limbo-land. The situation has been getting gradually worse over three years, as more and more decisions have been left untaken.

But things arguably reached tipping point in the weeks before Christmas when workers in the region's struggling health service embarked on industrial action to highlight low pay, spiralling waiting lists and staffing shortages. There was an unprecedented strike by nurses - the first ever in the UK - amid mounting public fury that patients are suffering while politicians continue to argue.

With more strike action planned, there is little doubt the health service crisis has lit a major fire under politicians' feet, providing further impetus to get back round the negotiation table.

- So what are the remaining disputes?

Same-sex marriage has effectively been taken off the table as a consequence of legislation passed by MPs at Westminster last year that ended the prohibition. The first marriages are expected in February.

The Irish language remains a key logjam. Sinn Fein has consistently made a standalone Irish Language Act a prerequisite of any deal to restore devolution. The DUP has expressed a willingness to legislate to protect the language, but only as part of broader culture laws that also include the Ulster Scots tradition.

There is a sense that the shape of a deal on language is there; it just requires sufficient political will from the two parties to make the required compromises to get it over the line.

Away from the language issue, all the parties accept that Stormont's structures and practices require an overhaul. However, they remain at odds on the shape of those reforms. One of the key disputes centres on the controversial petition of concern voting mechanism.

It was this issue, rather than the language row, that is understood to have prevented a pre-Christmas breakthrough. The mechanism, which enables large parties to effectively block change even if a majority of other MLAs agree to it, was a peace process construct designed to offer protections for minorities.

But there is a widespread sense that it has been abused, with parties using it for issues unrelated to the traditional community divide, such as on same-sex marriage and to prevent the censure of party ministers.

Talks faltered on plans to limit the use of the petition and make it more difficult to trigger. Proposals drawn up with the UUP, SDLP and Alliance secured the backing of Sinn Fein but failed to convince the DUP.

- And there's yet another deadline?

Yes, January 13. The three-year crisis has been marked by a series of missed deadlines, with the parties busting through successive cut-off points that were either imposed by the UK Government or set by legislation. There is another one approaching fast.

On January 13, legislation that has given civil servants extra powers to operate in the governance vacuum expires. Mr Smith will then be under a legal duty to call another snap Assembly election. Whether this deadline will prove any more meaningful than the others is yet to be seen.