The chapter investigates what options the (currently) devolved parts of the UK have when it comes to participation in the EU single market. The chapterdismisses the theoretical possibility of extending the Protocol on Ireland/Northern Ireland to Scotland and Wales as this would raise difficult questions around border management, state aid, and would call into question the UK internal market. Hence the only realistic options for continued (full) participation in the single market for the three devolved parts of the UK would be secession from the UK. While secession for Northern Ireland would lead to unification with an existing EU Member State, secession for Scotland or Wales would not necessarily lead to EU membership. Instead Scotland (on which this part of the paper focuses) would have tough choices to make. As with Northern Ireland, the management of the land border between Scotland (in the EU or EEA) and England (outside the single market) would become crucial. The chapter explores how checks on persons could possibly be avoided and draws up a possible solution that might avoid checks on goods on border crossings between Scotland and England. The chapter shows that the border would be easier to manage if Scotland settled for EFTA/EEA membership instead of full EU membership, but that this might not be politically desirable. The chapter further argues that even with Scottish membership of the EU, the border could remain almost invisible and permeable if Scotland managed to obtain an opt-out from having to join the Schengen zone.