One of the strikingly iconoclastic features of actor-network theory is its juxtaposition of the claim to be a realist perspective with denials that supposedly natural phenomena existed before scientists "made them up." This paper explains and criticizes such arguments in the work of Bruno Latour. By combining referent and reference in the concept of assemblages, Latour provides a superficially viable way to reconcile these apparently incompatible claims. This paper will argue, however, that this conflation of referent and reference leads Latour’s ontology into difficulties that can only be resolved by abandoning it in favor of a more conventional—critical—realism.