Frequency of occurrence is known to have many effects on speech production [see J. Bybee, Phonology and Language Use (Cambridge, 2001)] including vowel quality, overall duration, rate of deletion, assimilation, coarticulation, etc. The current work addresses voice-onset time (VOT) in words with differing lexical frequency estimates from published materials and addresses whether words in a list exhibit similar effects to words in sentential context. Four talkers produced 20 low frequency words and 10 high frequency words four times each in isolation and again in non-idiomatic, sentential context. VOT was measured in monosyllabic content words with initial /t/. Results show that frequent words (e.g., talk, table) have a mean VOT roughly 10 ms shorter than less frequent words (e.g., talc, taint) (p<0.01). The effect was significantly stronger for words in a sentence (e.g., He will talk to his supervisor) than in a list. These findings are consistent with linguistic theories that propose detailed auditory representations for words and finely controlled productions, but are in conflict with traditional, abstract phonological representations.