Born in 1931, he participated of catholic students movements and became architect and urban planner in 1957. He worked then in research on standards of living and developpement and in planning for the State Government of São Paulo. In 1963 he became the director of planning for the brazilian Land Reform. After the military coup in 1964, he worked in the planning of the National Conference of Bishops. Forced into exile at the end of 1966, he lived initially in France, teaching and in the Catholic Committee against Hunger and for Developpment. In Chile from 1970, he worked in the UN Economic Commission for Latin América, till the overthrow of Allende. Returning in 1974 to France, he coordinated the "International Study Days for a Society overcoming Domination", launched by the Brazilian Bishops, to facilitate world intercommunication among struggles against oppression. In Brazil from 1982, he was advisor to Cardinal Evaristo Arns in São Paulo. One of the founders of an Association for Solidarity in Unemployment, he was activist of the popular participation in the drafting of the new Brazilian Constitution. After being elected twice, in 1988 and 1992, as local councillor in São Paulo for the PT (Brazilian Workers' Party), he returned to work with civil society. Executive Secretary to the Bishops Conference Commission on Justice and Peace from 1996, he worked collecting one million signatures in a Bill of Popular Initiative against electoral corruption, approved in 1999. He was one of those who conceived and implemented the idea of the World Social Fórum. He received in 2006 the Right Livelihood Award, known as Alternative Nobel Prize.