A lot of hassle and potential cost for a lot of people.
The government's spent the afternoon giving details of what might need to happen, if there was no deal with the EU.
There's no guarantee you'd be able to avoid big phone bills if you use your mobile abroad, although ministers say they'd cap any data charges at £45 a month and some of the firms say they won't change prices.
If you want to go on the road on the continent, you might need an International Driving Permit.
If you want to jump on a cheap flight for a last-minute weekend, better check you have six months left on your passport, or you might be turned back.
If there isn't a deal, many products tested in the UK after Brexit will have to go through the same process again - but with an EU authority in charge.
The list of what might have to happen is a very long one. And some of the trickiest implications, like what would happen to planes flying between European and British skies, haven't even been published yet.
And as the French foreign minister suggested, the Eurostar might not be able to run, and yes, planes may not be able to fly if a resolution can't be found.
Publishing the papers are part of the government's plan to look like they are prepared for the potential shock and disruption of the negotiations failing.
And indeed, for some in government, publicly detailing those preparations is part of a tactic to suggest that they have a way out and are ready to walk away, if Brussels doesn't budge.
What ministers won't say, however, is how much money we might have to pay the EU if there were to be no deal.
The Brexit secretary and the prime minister have both repeatedly said that the estimated price tag of nearly £40bn if there is a deal would not be paid in full.
But they refuse point blank to give an assessment of how much it would be, if we walked away without an agreement.
The reality is the cost would probably still be many billions, and it would take lawyers many, many years to be able to agree on it.
In that situation, the government would be walking away without being able to tell MPs or the public how much we would still have to stump up.
Ministers' belief, however, is that the chances of there being no agreement are now relatively small.
They are hopeful that next week EU leaders will give helpful hints at a special meeting in Salzburg.
On Thursday, the Brexit secretary told me he believes the EU will meet the UK "half way" on the Irish border issue, which for many many months has been the trickiest issue of all.
Yet there is a long way to go until he, or anyone in government, can be sure. And don't doubt that many Tory MPs are adamant they simply won't vote for the kind of proposal Theresa May has put on the table.
One senior MP told me: "If people in Number 10 haven't made clear to her that 'Chequers minus minus' isn't going to get through the Commons, then she is getting the wrong advice."
After all, there are two kinds of "no deal" - one seems very unlikely, where the EU and the UK simply can't agree. The prime minister comes back to Parliament and says: "I'm sorry, I tried, but it just won't wash."
But the other is that Theresa May comes back with a deal but her party, and Parliament, chucks it out.
The political climate would be different in those two cases.
But in the potential chaos of either, the hassle outlined on Thursday might just be the start.