This article reports partial results from a research that analyzes the perceptions about Brazilian legal system
among a group of South Americans immigrants living in the Greater São Paulo area. More specifically, the research gather data on the perception of reception and stay of foreigners in the country and, once they are established in Brazil, the problems related to the access to fundamental rights. The research focused on vulnerable South American immigrants, in order to do an analysis of the effectiveness of Mercosur Residence
Agreement. The article reports the methodological difficulties about the study of international migration, especially when considering the vulnerable migrants. Besides, the article discusses the organization of the National Conference on Migration and Refuge, a governmental event that provided an opportunity for immigrants to have a direct participation in debates about legal issues related to foreigners in Brazil.