Confused about Labour's position on Brexit?
Brexit is the defining political issue of our time, and it is currently causing the biggest headache for the government.
But Labour's position, or some might say lack of one, on some of the big questions about life after the EU will also come into focus.
30 MPs along with other high-profile figures from the party have signed a letter urging Jeremy Corbyn to commit to staying in the single market and the customs union after Brexit.
Elizabeth Glinka has been taking a look.