Welcome to the Applied Linguistics (AL) and Teaching English to Speakers of Other Languages (TESOL) Program at Teachers College, Columbia University. The AL and TESOL program is interested in questions related to the nature of language as a biological, physical, or psychological phenomenon, as well as to questions concerning how language is used by native speakers and language learners as an interactional, social, or cultural phenomenon. The AL and TESOL program is also deeply concerned with how first and second languages are learned, taught, and assessed in a wide range of real-world or laboratory contexts.