Two experiments examined phonological priming in children and adults, using a cross-modal picture-word interference task. Pictures of familiar objects were presented on a computer screen, while interfering words (IWs) were presented over headphones. In terms of their relation to target pictures, IWs were either phonologically related, unrelated, neutral (the word go), or identical. Ninety children (30 aged 4;11 to 5;11, 30 aged 6;11 to 7;11, and 30 aged 9;5 to 11;9) and 30 adults were instructed to name the pictures as quickly as possible while ignoring the IWs. In Experiment 1, related IWs shared onset consonants with the names of the pictures. Across ages, participants named pictures faster with related IWs than with unrelated IWs. In Experiment 2, related IWs rhymed with the targets. Here, only the youngest children (five to seven-year-olds) named pictures faster with related IWs than with unrelated IWs. The results indicate that priming effects reach a peak during a time when articulatory information is being consolidated in the output phonological buffer. The disappearance of the rhyme priming effect with age may reflect the gradual emergence of the onset as an organizing structure in speech production. This increased prominence of the onset can be viewed as one component of a just-in-time, incrementalist approach to speech production that allows adults to speak more fluently than children.