In EMU the question arises how countries will respond to adverse economic shocks. A statistical decomposition of output shocks in Belgium identifies the sectoral level as the main source of turbulence. This sectoral focus reduces the need for monetary, exchange rate and budgetary policies as macro-economic adjustment mechanisms but raises the issue of labour market flexibility. We show that wages fail to respond to sectoral and regional shocks. Similarly to the other EU countries, this absence of wage adjustments tends to amplify the regional divergence in production and employment performance, and can thus threaten political cohesion.