The Irish Question rises yet again, looming on the road to Brexit like the Sphinx on the road to Thebes. It threatens to devour those who cannot solve its great riddle: How do you impose an EU frontier across a small island without utterly unsettling the complex compromises that have ended a thirty-year conflict? The “people” part of the preliminary Brexit negotiations concerns the mutual recognition of the rights of EU citizens living in the UK and vice versa. The “money” part concerns Britain’s outstanding obligations to the EU budget and the calculation of the final divorce bill. Both are awkward and politically divisive issues, but it should be perfectly possible to reach a settlement.