The contribution provides a basic overview of Czech minorities abroad and a summarization of research results relating to this topic. Studies in language of those minority is a traditional part of knowledge of the language development. Attention is paid mainly to the description and analysis of language of one of those minorities, namely to the language of Czechs living in Vienna. The research of language of Viennese Czechs carried out from 1993 to 1997 brought information about contemporary situation of their language as well as information about tendencies of development on their language. Attention was also paid to the language of the Czech press in Vienna. Results of this research were published in the book U nás ve Vídni (In our Vienna: a rough translation; 1999).