‘Brexit: An Accident Waiting to Happen?’ will offer a historian’s view of the UK’s 2016 decision to leave the EU. It will ask whether the 44 year marriage between Britain and its partners has been flawed from the outset – and hence always likely to end in the divorce courts. Too simplistic an acceptance of this view will be rejected, however, with attention drawn to the gains that the UK has made through EC/EU membership, the constructive role that the British have been at times able to play in Brussels, and to the difficulty, until recently, of turning Euroscepticism into a winning electoral formula. The shorter term factors that gradually altered this situation will then be reviewed, with particular attention drawn to the altered position of the Conservative Party towards Europe, the collapse of the wider pro-European coalition, and the importance of immigration as a catalyst for popular disillusionment with EU membership.