Speech research suggests why phoneme segmentation is more difficult than syllable segmentation. This study provides direct evidence of a developmental ordering of syllable and phoneme segmentation abilities in the young child. By means of a task which required preschool, kindergarten, and first grade children to tap out the number of segments in spoken utterances, it was found that though ability in both syllable and phoneme segmentation increased with grade level, analysis into phonemes was significantly harder and perfected later than analysis into syllables. The relative difficulties of the different units of segmentation are discussed in relation to reading acquisition. (Author/SW)