The paper discusses the language policy of South Sudan against the backdrop of a sociolinguistic survey and various interviews with government officials in Juba, South Sudan, carried on in July-August 2013. After a presentation of the language situation of the country, the article focuses on Juba Arabic, its role and its unrecognized status as the most widely used lingua franca of South Sudan. The Constitution of the newly independent country nominally recognizes and enshrines the language diversity of the country, but does not come to grips with the very existence of Juba Arabic, an Arabic-based pidgincreole which is the only real unifying language of a vast portion of the country and the first language of the capital, Juba. Juba Arabic presents the usual problems of many creoles: it shows a high degree of individual variation, it lacks an established written code and norm, draws its lexicon – but not its grammar – from its lexifier and it does not bear an autonomous glottonym. As a special problem, its lexifier is Arabic, and it is therefore connected with a long-time " enemy: " Sudan. Building on those insights, the paper explores the official discourse behind the regimentation of the linguistic situation of South Sudan and assesses its impact on local linguistic practices.