Although the morphology of Homeric Greek has been richly described and rigorously analyzed, from both a synchronic and diachronic perspective, most of this work is tacitabout the relationship between morphosyntactic properties and their formal realization. This silence has perhaps been nowhere so troublesome as in the debates surrounding the morphosyntax of Homeric -φι(ν). One of the central issues in the scholarship on this suffix is the question of what category forms in -φι(ν) instantiate. Some maintain that they are adverbs; others contend that they are nouns. Evidence from agreement and prepositional phrases shows decisively that the latter analysis is correct. Building on this insight, I argue that -φι(ν) is an oblique case marker, which realizes genitive or dative case in the singular, dual, or plural. Crucial to this analysis is a realizational view of morphology, according to which all morphosyntactic information is independently available on the stem. I offer a novel synchronic analysis of Homeric -φι(ν) in Paradigm Function Morphology and demonstrate how this synchronic analysis in turn resolves a number of diachronic issues.