Ingrian and Livonian, two endangered Finnic languages, display a series of complex durational developments affecting vowels and consonants. The most pervasive of these changes (found in many Finnic varieties) is the gemination of a consonant preceding a long vowel or diphthong in the second syllable of disyllabic words, e.g. standard Finnish kalaa 'fish' partitive sg. vs. Ingrian kallaa. Kiparsky (2006) suggests that lengthening of the consonant preceding the long vowel reflects a foot optimization strategy to eliminate an ill-formed trochaic foot consisting of a light stressed syllable followed by a heavy unstressed syllable. The situation in Ingrian and Livonian, however, is complicated by additional less transparently motivated processes such as the lengthening of a short vowel in the second syllable following a CV initial syllable (a phenomenon also encountered elsewhere in the Finnic family), the extension of consonant lengthening to novel contexts (consonant clusters in both Ingrian and Livonian, consonants after long vowels in Ingrian, and trisyllabic words in Ingrian), the shortening of the long vowel originally triggering lengthening in Livonian and sporadically in Ingrian trisyllables, and the development of a glottal stød feature preceding lengthened voiced consonants in Livonian. This paper presents phonetic data from the various lengthening processes occurring in Ingrian and Livonian. It is shown that different lengthening processes display different durational distributions, some of which are more categorical in nature than others, as proposed by Kiparsky (2006), and some of which have interacted to create a restructuring of the phonemic system. We will also consider functional motivations and the mechanism of historical change behind the quantitative alterations in both languages.