Three picture-word interference (PWI) experiments assessed the extent to which embedded subset words are activated during the identification of spoken superset words (e.g., "bone" in "trombone"). Participants named aloud pictures (e.g., "brain") while spoken distractors were presented. In the critical condition, superset distractors contained a semantically related embedded word (e.g., "charm," which contains "arm"). In Experiment 1, supersets and subsets differed by one phoneme ("charm/arm") and interference effects were obtained when subsets were embedded at the beginning or end of the superset. In Experiment 2, the subsets and supersets differed by three or more phonemes. Interference was obtained for final embedded words aligned with a syllable boundary of the superset ("acrobat/bat") but not otherwise ("pioneer/ear"). In Experiment 3, the size of these PWI effects was compared to the effects obtained with the subset words presented in isolation. The implication of these findings for theories of speech perception and production are discussed. We also consider the possible advantages of the PWI task over cross-modal priming and "visual-world" procedures when studying these issues. (Contains 3 tables and 2 footnotes.)