The DLC concept also allows teachers and researchers to take into account various kinds of impact that multilingualism has on education. One impact of DLC is to illuminate how literacy teaching is to proceed in multilingual classrooms, with learners coming from traditions of literacy that might differ markedly from the official curriculum. Relatedly, DLC allows us a perspective on how languages are taught, and what is the relation between all the languages in the lives of learners compared to those present in the curriculum. This linguistic diversity ranges from the language(-s) of the state and the languages of population groups within the state, whether small and scattered, or large and concentrated, whether immigrant or indigenous. This chapter looks at the complexity of literacy and language education practices in light of the view among political theorists and economists that world systems are converging, that the world is becoming 'flat'. When we look at the world of culture and communication, a world of differentiation and expansion of diversity is revealed. DLC is both a heuristic for representation of the specific clusters of languages that educators need to manage in an ever larger number of societies, but also a theoretical and analytical tool for a deeper academic understanding of clusters of multilingualism, allowing us to identify practices of language and literacy and how they are linked. [For the complete volume, "Dominant Language Constellations Approach in Education and Language Acquisition. Educational Linguistics. Volume 51," see ED660754.]