This paper presents new data, in the form of four indices, on liberalization policies and the independence of regulators for a cross section of countries. These indices are combined with a comprehensive set of performance, institutional and political data to analyze both the determinants and the impact of telecommunications policies. We find that liberalization policies are negatively associated with the degree to which countries have an interventionist tradition, but not with the partisan ideology of reforming countries per se. We also find that countries where the institutional endowment constrains less the behavior of the executive bodies, and countries with a stronger incumbent, are more prone to create truly independent regulatory agencies. There is weak evidence that the creation of independent regulatory agencies has a positive effect on network penetration when we take into account the endogeneity of regulatory independence.