For a number of years now, Belgium has been a country of Muslim immigration, whereas, traditionally, Egypt has been a multi-religious country. Nevertheless, these two countries have their legal systems of Romano-Germanic origin in common. On the other hand, the attitude of the authorities (including the legal authorities) in dealing with institutions and legal pluralism, and more especially the role of Islamic norms seen as a source of law, cannot be explained in the same fashion. In Belgium, recourse to the protection of basic rights (religious freedom, liberty of expression) enables the tribunals, on a case to case basis, to apply the rules of a form of legislation put forward as Islamic. In Egypt, on the contrary, an internal situation which superimposes Islamic law (shari'a) on positive legislation enables both those brought before the court and the judges to act on different normative levels. We first establish the context within which the role-players (both Belgian and Egyptian) on the legal scene took recourse to the Islamic origins of law. By so doing, we should like to offer a comparative reading of the way in which the courts and the tribunals in the two countries handled legal adherences and identities. This comparison will be supported by a concrete example taken from recent jurisprudence: the issue of whether headscarves may be worn in state schools.