Control of natural resources, especially oil and gas, has been a major issue in the consideration of underdevelopment. In the present commodity boom, some Latin American economies are reforming their resource exploitation regimes, especially those issues linked with foreign capital share. The purpose of this report is to analyze these changes in the Bolivian and Brazilian oil and gas sectors in order to answer such questions as: Which property system combining public and private capital is the most suitable? Which regulating framework can guarantee a sustainable increase in output and investment? Our analyses lead to the conclusion that the regulatory framework can establish a particular ownership structure that is considered favorable for improving the performance of oil and gas sector, but the internal dynamics and the historical trajectories of enterprises will also be determining factors that interact with the given regulatory framework, generating mixed results. (C) 2013 Elsevier Ltd. All rights reserved.