On June 23, 2016, 52% of UK voters opted to put their country on the path to leave the European Union by March 29, 2019. This result was a surprise to many and went against the advice of the vast majority of economic experts and business leaders. Two years later, and after a remarkable period in UK politics, key questions about the future relationship between the UK and the EU remain unresolved. Various models have been proposed; the latest one by Prime Minister May triggered the resignation of a number of key ministers. All of them struggle to deal with a fundamental tension: how to square barrier-free trade between the UK and the EU, especially across the border between Ireland and Northern Ireland, with both full policy sovereignty for the UK and adherence to the “four freedoms” at the heart of the EUs Single Market. A “no deal” Brexit by default remains an option, despite the costs to UK businesses and the wider UK economy.