In this paper we test whether a reallocation of government budget items can enhance long-term GDP growth in a set of European countries. We apply modern panel data techniques to the period 1970-2006, and we use three alternative dependent variables in a growth regression: economic growth, total factor productivity and labour productivity. Our results are able to identify also the distortions induced by public expenditure in the private factors allocation. In particular, we detect a strong crowding-in effect associated to public investment, which have enhanced economic growth by boosting private investment. We also associate a significant dependence of productivity on public expenditure on education as well as the role of social security and health issues in growth and the labour market.