In this chapter we present a brief overview of the literature on interpreting focused specifically on issues and questions raised by this literature about the nature of bilingualism in general. It is our position that research carried out on interpreting—while primarily produced with a professional audience in mind and concerned with improving the practice of interpreting—provides valuable insights about complex aspects of language contact that have not been thoroughly addressed by the existing literature on bilingualism. Examination of the literature emphasizing a category of bilinguals, who have been referred to as “true” bilinguals (Thiery, 1978a, b), provides perspectives on both individual and societal bilingualism that can complement, and possibly refocus, some current views of the linguistic, psycholinguistic, and sociolinguistic characteristics of language contact. For applied linguists who study language minority populations around the world, the literature on interpreting suggests important new directions for research focusing on areas such as the process of high level development of two languages in diglossic contexts; the effects of instruction on the development of nonsocietal languages; the nature of language transfer; and the characteristics of communication between speakers of societal and nonsocietal languages.