The question of Muslim women marrying non-Muslim men in Europe poses numerous challenges to Islamic law and ethics. Religious authorities continue to ban these marriages and recent evidence from collective bodies of fatwā suggests that to date there has been little attempt to revise this prohibition. The issue has grown in importance in light of public debates on integration, communitarianism and segregation in Europe. Whilst some research has been carried out on Muslim women marrying non-Muslim men, no single study exists which closely reads the current arguments used to justify it in a European context or attempted to investigate the ethical and social logic of the ban on this type of marriage. It is argued here that Muslim jurists and theologians re-invent the discursive consensus and tradition to sustain in-group moral economy.