The two-year countdown began Wednesday toward Britain's official departure from the European Union, raising a question: What happens now?
There will be deals to work out, among them trade, legal agreements and the rights of British expatriates living in EU nations. British Prime Minister Theresa May called the move to leave the EU, dubbed Brexit, a "unique opportunity" to "shape a brighter future" for the country. But there will likely be several pitfalls to navigate before March 29, 2019, the deadline for signing off on a final agreement.
"There is no precedent for this." said Kal Raustiala, professor of law and director of the Burkle Center for International Relations at the University of California, Los Angeles. "It's hard not to imagine that this wouldn't be one of the most protracted and difficult negotiations in European history. This is going to be really, really quite complex."
Here's a look at how and why Britain got to this point and the rocky road ahead.
