The paper explores how to integrate a Transnational Labour Inspectorate (‘TLI’) dealing with transnational private instruments of Multinational Enterprises (‘MNEs’) into the International Labour Organization (‘ILO’). After exploring monitoring initiatives with roots in public international organizations, we will argue that from an international law perspective on international legal personality such activities can be justified. Under the qualification of ‘subject normation’, as we dub these activities, we will argue that the ILO is the best situated locus to embed a system to inspect commitments MNEs voluntary adhere to in their CSR strategies, including Global Framework Agreements. Finally, we explain how the TLI as we envisage it could fit within the existing system of enforcement and compliance monitoring of the ILO.