This chapter discusses the consequences of introducing laws of language co-officialization for the immigration languages to Brazil, at the municipal level, especially the German languages. It traces the sociolinguistic history of these languages showing that they are now spoken primarily in Brazil, as what one might call 'Brazilian languages'. The migratory flows from German states to Brazil started around 1824 and led to the influx of speakers of several German languages, which were considered to be 'dialects' in Europe at that time. The German colonization of southern and southeastern Brazil covered vast regions. Partially autarchic social units were developed, with original institutions such as community schools and churches. The chapter explores the unexpected effects of the policy processes that were set in train in 1988, and examines how the officialization of minority languages came up against complex issues, as the Brazilian constitutional process has unfolded. One of the greatest impacts of this policy process has been on the immigration languages.