The state reform in Brazil started to be outlined with the approval of the Law of Concession of Public Services, Law 8987 of February 13, 1995. The articles provided for in this first initiative needed to be more detailed in order to allow resources from the private sector to increase the supply of electric power. Therefore, four months later, in July 7, 1995, Law 9074 was issued complementing the previous legislation in a special chapter specifically concerned with the electricity market. In the following year, Law 9427 of December 26, 1996 created the Brazilian Electricity Regulatory Agency (ANEEL), whose regulation was defined by Decree 2335 of October 6, 1997. The decree establishes the directives to be followed by ANEEL, its powers and responsibilities and its governing and administrative structure, as well as the principle of decentralization that allows the regulatory agency to extend its action throughout the Country.
On November 28th, 1997, ANEEL had its Bylaw approved by Ordinance MME 349. This Bylaw was later modified by Resolution 267, of July 13, 2001 and then by Normative Resolution 116 of August 29, 2004.