This paper provides background information on a number of topics foreseen for discussion at the Foundation Forum 2017 'Converging economies, diverging societies? Upward convergence in the EU'. The term ‘convergence’ first appeared in the Treaty on European Union (Maastricht Treaty) in 1992 in relation to the convergence – primarily in terms of monetary and fiscal indicators – required for membership of the Economic and Monetary Union (EMU). Moreover, in the preamble to the Treaty, Member States ‘resolved to achieve the strengthening and the convergence of their economies’. Technically speaking, convergence is a process that tends towards parity and implies faster rates of growth for those at lower levels. Market integration tends to both bind Member States together and increase the standard of living in all countries. However, it by no means guarantees convergence, as some well-off Member States may benefit more than others. Integration can also give rise to inequalities within Member States, with some sectors gaining and others losing. This may also be reflected in regional disparities. Both these distributional risks increase with deeper integration.