The UK’s capital markets play a central role in Europe’s financial system. Brexit now threatens to detach the EU from the UK. In this policy paper Philipp Ständer analyses the economic and political implications of Brexit for Europe’s Capital Markets Union (CMU). First, the paper analyses from an economic point of view which capital market segments would be most affected when the UK loses access to the Single Market. Second, it compares the political support for CMU before and after the Brexit referendum and assesses how the UK’s retreat from the political process may affect the CMU agenda.