The article author takes up again the issue of Polish-Portuguese bilingualism and recalls his research conducted in Brazil in the mid-nineties of the 20th century. He begins with a presentation of the research methodology and its territorial conditioning. He presents bilingualism as a group phenomenon, characteristic for most Brazilians of Polish descent (the author of the article highlights the differences between big cities, small towns and colonies). Next, he recalls the ways of becoming bilingual, which enables him to analyse individual cases of bilingualism and its variability over time. The article concludes with the three case studies described in the monograph published in 2003. The author presents successes achieved by the described people due to their knowledge of Polish language.