In this chapter, we review some of the most commonly invoked educational challenges of working with children who are bilingual or multilingual and point to their moorings in a normative, strictly monolingual perspective – a monolingual bias. We then move on to present an alternative, and radically social, understanding of childhood multilingualism firmly based in the growing body of CA-oriented studies of bi- and multilingual interaction in early childhood education settings. Drawing on data from different educational contexts, we examine the manifold ways that participants make use of language alternation, showing how the availability of more than one language can be used productively, as a resource that supports learning. We round off the chapter by highlighting some implications for educators who work with multilingual children. Although the extracts provided in the text are taken from settings where both teacher and children share more than one language, the affordances we discuss will be of relevance to educators who do not have access to children’s first language.