The Spanish Opposition of a tap [r] and trill [R] is unusual in several respects. Most contemporary phonological analyses postulate a single phoneine /r/, deriving the phonologically distinctive intervocalic trill from geminate /r-r/. This type of analysis fails to address several important issues. These include the fact that [r] is the only Spanish consonant which occurs onsetinitially in word-internal position but cannot occur word-initially, and the fact that the intervocalic trill [R] is clearly onset-initial, thus requiring a derivation which radically changes the syllabic structure from an underlying heterosyllabic geminate to a superficial onset-initial trill. In the present study an attempt is made to unify surface [r] and [R] via reference to syllabic templates, which allow a maximum of two consonantal elements in the onset. Manifestation s of [R] are analyzed äs maximizing the syllabic template, while intervocalic [r]is derived from a more marked underlying structure, preattached to the prosodic skeleton. Non-preattached /r/ is expanded to a dual structure, which ultimately produces [R], in appropriate contexts. The relatively marked nature of the [r]-[R] Opposition is demonstrated, and it is claimed that this Opposition is not a carryover from Latin quantitative distinctions.