Structural Funds are the most intensively used policy instrument by the European Union to promote economic growth in its member states and to speed up the process of convergence. This paper empirically explores the effectiveness of European Structural Funds by means of a panel data analysis for 13 countries in the European Union. We show that - on average - Structural Funds are ineffective. For countries with a 'proper' institutional framework, however, Structural Funds are effective. The latter result is obtained for a wide range of conditioning variables, such as openness, institutional quality, corruption and indicators for good governance. It is robust to a wide range of robustness tests. © 2006 Blackwell Publishing Ltd.