While critical histories of international law on the interwar period have focused primarily on nationalism, early conceptions of the right to self-determination, and the dynamic of cultural difference, this article brings to bear another dimension that shaped interwar governmentality of legal institutions, namely class subjectivity. How did international institutions manage ‘class’ in a colonial context and at the height of the ‘self-determination talk’ of the interwar period? Through this inquiry, I study the details of the concrete practices of the International Labor Organization (ILO) in one of its earlier missions sent to Egypt in the 1930s. The claimed success of the ILO’s intervention hinged upon shaping a new politics of expertise through law that divided a fluid and hybrid sphere of social activity into rigid and separate domains: the technical and the political.