The volume offers a collection of the most recent research coming from scholars and practitioners in the field of multilingualism research in various contexts of natural/immersion environments, school/formal instruction, grounded in multilingual societies and individual multilinguality of semi-monolingual countries. The studies included in the book constitute an exemplification of new methods of research used (e.g., narratives, visualizations, metaphors) as well as new approaches to multilingualism (affordances, dominant language constellations). The volume is divided into four parts: (1) Part One focuses on different dimensions of multilingualism; (2) Part Two zooms in on the concept of affordances and their role in the development of multilingual competence; (3) Part Three concentrates on dominant language constellations in different contexts; and, finally, (4) Part Four shifts the focus to instructional practices in teaching multiple languages.