Global Union Federations are international organisations that group national or regional trade unions in specific industrial or professional domains. Global Union Federations play an active role within the international labour context, but they might be less well-known than other supranational organisations. This thesis aims to provide a general overview of Global Union Federations. As novice interpreters ourselves, we consider this environment as an interesting opportunity to acquire work experience after graduating. In light of that, this thesis is divided in two main parts. The first part presents a basic guide to Global Union Federations. In the second part, three of the GUFs based in Geneva are analysed through the eyes of their chief interpreter.