To what extent is the European Union an effective actor in its interaction with international organisations? Moreover, what mechanisms does it use to promote its policy agenda and export its policy preferences? Existing studies assess the influence of EU policy ideas with regards to third countries or regions, but tend to ignore its influence on international organisations. To fill this gap, the present chapter examines the way the EU seeks to diffuse its policy preferences to the International Labour Organization (ILO) with regard to the policy agenda of flexicurity by using emulation as a diffusion mechanism. Making use of a discursive institutionalist approach, we demonstrate that the relationship between the EU and the ILO is a dynamic one, and that EU actorness within the ILO in the area of flexicurity has been successful. The chapter suggests that the EU’s participation in the ILO has resulted in some kind of ideational ‘Darwinism’, whereby the ILO emulated the EU policy idea of flexicurity and at the same time adjusted it in order to facilitate its own purposes and priorities. The evidence also suggests that the EU’s long-term participation in, and loyalty to, the ILO increased its voice in it.