Cognitive Linguistics (CL) is an approach to the study of language informed byboth linguistics and psychology. It describes how language interfaces with cogni-tion, and how it adapts in the course of language usage, phylogenetically in lan-guage evolution, ontogenetically in language acquisition, and moment-to-momentin situated, on-line language processing and performance. Second LanguageAcquisition (SLA) involves the study of the cognitive representations and mech-anisms of second language processing, their time-course of acquisition, and,where possible and feasible, their relevance to instruction.The Handbook of Cognitive Linguistics and Second Language Acquisition bringsthese two areas of theory and research together