This text analyses the development o f organic farming in Brazil.  Itfshows the great variability of social models of organic production recognised by Brazilian Law:  organic, agroecological, ecological or biodynamic agriculture, pcrmaculturc etc. It dcpicts how the political and social concerns in the spheres of family farming and environment caused the reorganisation of production systems, in the agricultural  practices and in the new relationships with the market and with natural resources.  Based on interviews with farmers and stakeholders involved in the development of various organic systems, we qualified the related models of production as well as the related social and cultural values.  Wc also present some aspects of the historical roots of this agroecological  movement and the way family farmers adapt to the new challenges of ecological production.