This paper investigates the role played by public capital in increasing the productivity levels in Italy. For the construction of the regional series for the public capital over the period 1996-2002, the study benefits from the use of the rich dataset on public expenditure, recently published by the Dipartimento per le Politiche di Sviluppo of the Italian Ministry of Economy and Finance. On the basis of estimated panel production functions the results point out that public capital has a positive and significant effect on production. Moreover, the effects of all production factors vary considerably between the Centre-Northern regions and the Southern regions of the country. In particular, while private capital is more effective in the South, public capital and labour exhibits elasticities much higher in the Centre-North with respect to the Mezzogiorno. The disaggregation of public capital in economic categories signals a significant different impact in the two macroareas. When the analysis is carried out by distinguishing among government levels it turns out that the decentralized administrative bodies are much less efficient in the South in delivering public expenditure.