The paper focuses on the analysis of the productivity and profitability of the natural gas distribution in Italy between 1994 and 1999. The period covers the years preceding the liberalisation act. The dynamic of efficiency and the characteristics of cost are analysed in a general framework and then associated to various organisational arrangements involving the type of ownership, the degree of diversification and the size. The main results outline a marked profitability but a low growth in the total factor productivity. The reason is to be searched in the price regulation system. More in detail, the public firms and the specialised ones show greater performances than their counterparts. Quite ambiguous influence is exerted by size variable.