The spokespersons of Western Europe’s Muslim communities face the imperative to garner legitimacy among distinct, power-asymmetric audiences. They need to gain approval from the general public, whose opinions are ruled by secular liberal principles, and they need the support of their pious Muslim constituents, who uphold norms of Islamic authenticity. This thesis aims to situate the responses of Muslim political actors to these competing normative prescriptions. To do this, it disentangles the subtle trade-offs they need to negotiate between political pressures for a civil Islam and intra-community expectations of religious authenticity. This double-bind situation is unpacked through the case study of the Union des organisations islamiques de France (UOIF), arguably the most prominent organisation on the French Islamic landscape. Founded in 1983 by religiously observant students close to the Muslim Brotherhood, the UOIF rapidly evolved into an influential Muslim interest group looking for policy-makers’ recognition. Building on three years of ethnographic fieldwork as well as untapped material drawn from interviews, governmental archives and media analysis, my study argues that UOIF leaders progressively embraced a quest for political respectability. To this end, they sought to assuage suspicions about their Islamist filiation and subscribe to dominant secular- republican scripts about how ‘good Muslims’ should appear and behave. This strategy encompassed an array of ideological, organisational and tactical adaptations designed to establish the organisation’s credibility—from the construction of a respectable façade to the sanction of unruly members, and from cooperation with public authorities to theological reformulations. Aligning with dominant norms, however, was a costly process, and UOIF leaders consequently alienated factions within their Muslim followers, often finding themselves accused of compromising doctrinal principles and ‘selling out’ Islam. To capture this ambivalent strategy, I transpose the notion of the Politics of Respectability from predominantly North-American case studies on black elites to European Islamic contexts. Such a conceptual reformulation allows me to document Muslims’ political agency in hostile environments and clarify the inclusion dilemmas they face. In writing the first in-depth historical and ethnographic study of the UOIF, my ambition is twofold: to contribute to a substantial understanding of Muslim politics in minority contexts and to draw a more general framework accounting for the respectability politics of marginalised groups.