Negotiations
The Itaipu Hydroelectric Power Plant is the result of intense negotiations between Paraguay and Brazil which gained impetus in the decade of 1960. On June 22, 1966, the Ministers of Foreign Affairs of Brazil, Juracy Magalhaes, and of Paraguay, Sapena Pastor, signed the "Ata do Iguacu", a joint statement that proclaimed their willingness to study the hydraulic resources belonging to both countries on a condominium basis, "from and including the Salto de Sete Quedas to the mouth of the River Iguacu". In February of the following year, they created the Brazilian-Paraguayan Joint Technical Commission for the implementation of the "Ata do Iguacu", with respect to the study of the development of the Parana. River.

The project
In 1970, a consortium formed by the U.S. firm IECO and the Italian firm ELC won the international tender for carrying out the feasibility studies and for preparing the plans for the project. The work began in February of 1971, and on April 26, 1973, Brazil and Paraguay signed the Treaty of Itaipu, the legal instrument providing for the development of the Parana River by both countries. A binational entity, called Itaipu, was created in May 1974 to manage the construction of the Power Station, and the work began in January of 1975.