The proposed research will investigate the development and evolution of the standard language ideology in Language Policy and Planning (LPP) texts of Luxembourg and the German-speaking community of Belgium (Eastern Belgium) with regard to the Luxembourgish language and the phenomenon of a Belgian Standard German, respectively. The research seeks to analyze if, how, and why LPP texts exemplify and legitimize the idea of a Luxembourgish standard language, on the one hand, and the idea of a Belgian Standard German, on the other hand. The evolution of Luxembourg’s and Belgium’s language policies and planning (LPP) goes hand in hand with the nation-building processes of the two countries. These two countries are now separate states, yet they share the similarity of being multilingual countries with an institutionalized trilingualism. The linguistic situation in Eastern Belgium has brought about the notion of a Gebrauchsstandard founded on German with Belgian distinctions (Küpper, Leuschner, Rothstein, 2017), whereas Luxembourgish is being standardized in Luxembourg. The research will encompass the post-WWII period to the present. The analysis of LPP texts and media reports from local newspapers of Luxembourg and Eastern Belgium will be based on Critical Discourse Analysis following Van Dijk (1997), Blommaert (2005), and Spitzmüller and Warnke (2011). The two chosen case studies can illustrate the evolutions in the standard language ideology in two politically and linguistically differing settings. A comparative study of the standard language ideology in the LPP related to Luxembourgish – as a language that is still going through standardization – and in the LPP concerned with Belgian Standard German, would provide a common framework for an understanding of the workings of the standard language ideology during the standardization process and its enduring effects in an already established standard.