This book is aimed at those who wish to delve into selected topics of language learning, teaching, and assessment in multilingual environments.

Our analysis begins with the observation that bilingualism and multilingualism are the norm rather than exceptions in modern societies. In this context, it becomes clear that the description and interpretation of the linguistic behavior of speakers who are learning languages or have a migratory background cannot be based on monolingual patterns, but rather on concepts, tools, and approaches that will holistically assess the bilingual-multilingual speaker.

Based on the above, this handbook focuses on seven topics that significantly contribute to a comprehensive study of language learning, teaching, and assessment, as well as the study of the consequences of interaction among various linguistic systems.

These include the most prominent theories of L2/FL learning, multilingualism, translanguaging, multi-competence, language attrition, Applied Cognitive Linguistics, and language assessment.

Understanding these topics does not require prior knowledge or familiarity, as the analysis of each chapter has an introductory and holistic character.