Sociolinguistic processes are inherent in the practice of interpretation. Interpreters, within seconds, receive, interpret, and reconstruct utterances between two languages, using their linguistic, social and cultural, or sociolinguistic, knowledge to create a successful, communicative exchange. This chapter describes some major and minor sociolinguistic studies of interpretation with the underlying assumption that interpretation itself constitutes a sociolinguistic activity from the moment an assignment is accepted, including the products and processes inherent to the task, reflecting variously issues of bilingualism or multilingualism, language contact, variation, language policy and planning, language attitudes, and, of course, discourse analysis.