So what exactly will happen now that Britain has voted to leave the EU?
Well it won’t mean border postings along Lifford, Bridgend and Pettigo overnight, for a start.
Under Article 50 of the EU’s Treaty , the UK will have to officially notify the European Council that it wishes to leave the EU.
This will start a two-year negotiation period, where the remaining 27 EU member states will negotiate, through Brussels, with the UK on the terms of its exit.
Many believe the talks could take longer than two years, but an extension would have to be agreed between all remaining EU states for this to happen.
It’s not clear how quickly David Cameron (if he remains in office) will give formal notification to the EU Council. The two-year period begins only when formal notification to leave has been received.
An EU Summit of leaders takes place in Luxembourg next week, so he may do it there. But he could also take longer, thereby delaying the start of the formal two-year period.
That formal period will essentially decide the status of post-Brexit Britain, and its relationship – politically and economically – with the rest of the EU.
What will a Brexit mean for Donegal and Ireland? Here’s what the experts are saying.
1: Let’s start with a positive
Many believe Dublin could win investment from companies that need to be based in an EU country in the event of a British vote to withdraw. The IDA is working to try and capitalise on a possible Brexit, by attracting multinationals with operations in London to Dublin. But the expectation is that the negatives will far outweigh the positives brought about by the possibility of increased investment
2: The initial impact will be around the currency
We’ve already seen a night of record movements on sterling.
The pound has been weakening which means it is more expensive for Irish exporters to sell into Britain. A Brexit vote will mean sterling will weaken even further, making Irish exporters even less competitive in the UK market.
3: Trade could be hit
With one country still in the EU, and the other not, that could pose problems. With €1.2bn worth of trade every week between the two countries, any new trade barriers would be unwelcome.
4: Northern Ireland
The border between Northern Ireland and the Republic would become an EU frontier. Could border controls be reimposed? Customs checks? Or could, as has been speculated, a border be introduced between the island of Ireland and Britain? For example, could travellers flying from Belfast to Britain need to go through passport control? These issues will be thrashed out in the two-year negotiation period. The Revenue Commissioners is already examining what it would need to do if a customs border is put in place.
Sinn Fein is already calling for a border poll.
5: Energy market
Questions have been raised about security of supply and the all-island Single Electricity Market.