In June 2016 the UK shocked the world by voting to leave the European Union. In our previous book (Brexit: Why Britain Voted to Leave the European Union) we told the story of what happened in the referendum and why it produced a leave vote. This book is a sequel to the earlier one and examines what happened after the decision was made looking at events up to the point that the UK formally left the EU in January 2020. This was a period of unprecedented political and electoral turmoil in British politics which for a period looked like it could shatter the party system. It encompassed three elections and three different Prime Ministers and unprecedented volatility in both Parliamentary and electoral politics. The book maps out the twists and turns of the Brexit process, both at the level of the political elites and among the mass public. It then goes on to examine the long-run antecedents of this momentous decision, using data that goes back more than fifty years. Finally, it speculates about the economic and poltical consequences of Brexit for the future, while taking into account the Covid Pandemic which itself added to the turmoil in British politics.