The State Banks were always cause of instability and imbalances in the National Financial System (SFN). Many adjustment programs were tried throughout the years, but they either only solved the immediate liquidity problems of that institutions or intervened on it without a effective plan of financial consolidation or extinction. This dissertation makesan analysis of the trajectory of the states financial institution from Natonal Financial Sytem's reform, in 1964, until the most recent restructuring program, The Program of Reduction of the State Public Sector Participation in a Bank Activity (PROES). Initially it describes the evolution of the State Banks and their role in the State Financial System (SFE). Then, it describes the main events that marked the implementation of the PROES. Finally, an empirical analysis is made of the eficiency gains generated by the PROES with a comparison of the banks situation before and after the introuction of th program. Such analysis is conducted both by unidimensional accouting measures and by multi-dimenional index obtained through the use of the econometric techniques.