^{At its core, this paper is an exploration of the morphology-syntax interface, and the question of whether the combination of linguistic units into words and the combination of linguistic units into phrases should be treated as distinct grammatical components or, alternatively, as parts of a uniform grammatical system. Specifically, the present survey takes lexicalism – a theoretical position maintained by morphologists and syntacticians for over forty-eight years – as the lens through which to understand the nature of the morphology-syntax interface and the goals of grammatical theory in general. By considering the predictions made by present formulations of lexicalism (e.g. the Lexical Integrity Principle (Bresnan and Mchombo 1995)) regarding morphosyntactic interaction, both cross-theoretically and cross-linguistically, I show that lexicalism does not properly characterize the morphology-syntax interface, and neither do linguistic theories based on lexicalist assumptions.}