The purpose of this article is to provide an explanatory account of the divide between enclisis and proclisis in pronominal clitic constructions in Romance and Semitic languages. The analysis is based on two fundamental assumptions: (i) clitics do not target designated prelabelled positions, but take maximal advantage of the available categorial structure; (ii) cliticization patterns are tightly dependent on the inflectional properties of the language, more specifically, on the feature content of the two functional categories, Infl and v. We show that the various asymmetries in clitic behavior can elegantly be explained in terms of the minimalist theory of movement, combined with certain formal hypotheses about the building of phrase struct...