Vowel duration is not contrastive in standard and regional varieties of Italian. However, vowels in stressed open syllables are longer than unstressed vowels or vowels in closed syllables. The increased duration is not equal in all positions. Most notably, the increased duration of a stressed open penultimate syllable is much greater than the duration of a stressed open antepenultimate syllable or a stressed final syllable, which has no noticeable duration increase. Nonetheless, phonological analyses of Italian have characterised length by a single rule (see for example Vogel 1986, Nespor & Vogel 1986) that lengthens non-final main stress vowels regardless of position. Phonetic studies, particularly Farnetani & Kori (1983, 1990) and Marotta (1985), pay closer attention to the duration of stressed vowels in different positions. Although their explanations of stressed vowel duration differ, the common theme is that duration differences are due to shortening vowels as a consequence of word compression or position (antepenultimate or penultimate syllable) in the word.

While the phonetic approaches account for differences in duration due to shortening, the phonological approaches propose lengthening with no regard for actual duration differences. The phonetic and phonological approaches to stressed vowel duration in Italian appear to be diametrically opposed. This paper proposes that lengthening a stressed vowel is the correct characterisation of duration differences in Italian, but there is no single rule that lengthens stressed vowels.