The General Law of Governmental Accounting in Mexico establishes the general criteria that govern this matter and the issuance of financial information of public entities. With this law, governmental accounting transcends its function as a simple generator of information to a role of integrator of public accounts at the different levels of government; in other words, governmental accounting becomes a key, permanent and recurring instrument for decision making.The purpose of this doctoral research was to evaluate the influence of the law on the financial performance of the federal entities and to identify the progress in accounting harmonization and the relevance for decision making as a reliable support in the administration of public resources, for the issuance of financial information and reports.