Dionisio Foianini Banzer (28 February 1903 – 23 November 2001)[1] was a Bolivian politician and businessman from Santa Cruz de la Sierra.

After studying pharmacy in Italy, where he came to admire Benito Mussolini's fascism,[4] Foianini returned to Bolivia before the Chaco War broke out and was put in charge of munitions manufacture.

During the war, he went on a secret mission to Argentina and organized Bolivian espionage behind Paraguayan lines.

When the war ended, Foianini organized the nationalization of the Standard Oil fields and set up a State Petroleum Board.

[6][7] The area called Dionisio Foianini Triangle on the border with Paraguay and Brazil is named after him.