This article examines the politics of governing forced labour. It develops and applies an approach drawing on Marx’s conception of the historical formation of ‘free’ labour in the process of ‘primitive accumulation’ and Gramsci’s conception of the ‘relations of force’. Viewed through this lens, rather than representing discrete ontological categories, the boundary between ‘free’ and ‘forced’ labour is repositioned as largely a contested and ambivalent artefact of governance. The concept of the ‘political relations of force’ highlights the ways in which such constructions are shaped by complex intersections between a diversity of different social forces. This approach is subsequently applied in an analysis of an International Labour Organization project on dealing with ‘traditional slavery’ in Niger.\ud \ud