What's Left to Be Settled Before Brexit (Quite a Lot)

With just over nine months to go until Britain is set to leave the European Union, the task of untangling itself from its neighbors is proving fiendishly complex. Former World Trade Organization chief Pascal Lamy says it’s like taking an “egg out of an omelet.” Brexit, as the withdrawal is known, poses risks to people and businesses that could get caught on the wrong side of a newly erected border. Deep disagreement among the British themselves on the best approach is complicating the process. With the U.K. set to exit the 28-nation bloc in March 2019, there are still more questions than answers about how Brexit will work. Here’s a guide to the trickiest issues.

Brexit means the U.K. must potentially give up one of the greatest benefits of being in the EU: the ability to buy and sell stuff with the 27 other members as if they were all one country. Leaving the EU’s so-called single market and its common customs rules could cripple cross-border supply chains that have been built up over decades. Cars assembled in the U.K., for example, are on average only about 40 percent British-made, and parts can cross borders many times in the process. The EU is the destination for about half of U.K. exports.