Independent experts are routinely appointed by international organisations for specific short-term assignments. Existing scholarship has studied their career trajectories, accumulation of resources, and mobility across occupational settings to explain their power and capacity to pursue their own agendas. However, it has neglected the fact that many transnational professionals not only move between professions but also practise them simultaneously. By using the example of the United Nations special rapporteur, an independent human rights expert, this article addresses this under-theorised feature by theorising them as plural professionals, or actors who practise multiple professions simultaneously. This multiple positioning in several professional settings at once can create tensions in how they approach their work. But, as I argue, it is also the source of their expert independence, rooted in a transnational social space connecting multiple professional identities, resources, and skills. Independence viewed through this lens is a socio-historical category which is made up of the combination of professional, biographical, and institutional resources as embodied and strategically mobilised by plural professionals. This argument builds on my original dataset of the professional biographies of 122 thematic special rapporteurs and 30 biographical interviews.