Theo du Plessis is professor emeritus in the department of South African Sign Language and Deaf Studies at the University of the Free State. His areas of interest include Language policy - Decision-making on language function and status in different language usage domains, legislation, state administration, administration of justice, education and non-official domains; Language planning - Corpus planning (language structure), status planning (function and official status), prestige planning and recruitment planning (education); and the politics of language - Politics of language and language with/in politics