Left-of-center party founded by Arturo Frondizi, president of Argentina from May 1, 1958 to March 29, 1962, when he was overthrown by a military coup, and Rogelio Julio Frigerio, known for his developmentalism theories. Frondizi chaired the Intransigent Radical Civic Union, which he split off from to form MID. Party is led by Juan Pablo Carrique [Movimiento de Integración y Desarrollo (MID)].