Anselm's Ontological Argument fails, but not for any of the various reasons commonly adduced. In particular, its failure has nothing to do with violating deep Kantian principles by treating ‘exists’ as a predicate or making reference to ‘Meinongian’ entities. Its one fatal flaw, so far from being metaphysically deep, is in fact logically shallow, deriving from a subtle scope ambiguity in Anselm's key phrase. If we avoid this ambiguity, and the indeterminacy of reference to which it gives rise, then his argument is blocked even if his supposed Meinongian extravagances are permitted. Moreover it is blocked in a way which is straightforward and compelling (by contrast with the Kantian objections), and which generalizes easily to other versions of the Ontological Argument. A significant moral follows. Fear of Anselm's argument has been hugely influential in motivating ontological fastidiousness and widespread reluctance to countenance talk of potentially non-existing entities. But if this paper is correct, then the Ontological Argument cannot properly provide any such motivation. Some of the most influential contributions to ontology, from Kant to Russell and beyond, rest on a mistake.