This study was an investigation of the role of language proficiency and automatization of language skills in the use of spontaneous rehearsal strategies by children who are deaf. Thirty-one profoundly deaf children, 7 to 13 years old, were given a serial recall task, a test of language proficiency (the Language Proficiency Profile—I), and a rapid automatized naming (RAN) task. Similar to previous studies, when the data were examined by age, an apparent developmental lag was observed in the children's spontaneous use of a cumulative rehearsal strategy. Logistic regression analyses further demonstrated that age was actually a nonsignificant predictor of rehearsal use, but that both language proficiency and the automatization of language skills were highly significant predictors. In subsequent hierarchical analyses, automatized language was a partial mediator of the language proficiency → rehearsal use relation. These results provided support for the view that automatization of language skills is an important and perhaps necessary contribution to the relation between language proficiency and rehearsal use, but that other additional aspects of language proficiency also affect the child's use of a strategy. These findings were discussed in relation to Cummins’ (1984) model of language proficiency.