This study investigated sensitivity to rhymeand phoneme among readers and nonreaders with Down syndrome (DS) and normally developingchildren. Three tasks were administered toevaluate sensitivity to rhyme and phoneme: arhyme detection task, an initial phonemedetection task, and a middle phoneme detectiontask. Results for the normally developingchildren replicated the results of previousstudies suggesting that the ability to detectrhyme is a developmental precursor of theability to detect phonemes. Although all taskswere very easy for the children who had alreadystarted to read, the nonreaders found the rhymedetection task significantly easier than eitherthe initial or the middle phoneme detectiontask. On the other hand, there was scarcelyany indication that the individuals with DSfound the rhyme detection task easier thaneither one of the phoneme detection tasks.While all tasks were very difficult for thenonreaders with DS, the DS individuals who hadalready started to read found the rhymedetection task significantly more difficultthan both the initial and the middle phonemedetection tasks.