Theories in Second Language Acquisition surveys the major theoretical approaches currently used in second language acquisition (SLA) research, providing a systematic and coherent presentation in a single source. Each chapter follows a consistent chapter model constructed around the same set of questions, including "What is the Theory?" "What are the major constructs?" "What counts as evidence?" "What are the common misunderstandings about the theory?" The answers to these questions are written at a basic level by a leading expert in the respective theoretical model. As a result, the volume as a whole presents complex ideas in an accessible manner.