Purpose: To examine the production of plural morphology in children acquiring a dialect of Spanish with syllable-final /s/ lenition with the goal of comparing how plural marker omissions in the speech of these children compare with plural marker omissions in children with language impairment acquiring other varieties of Spanish. Method: Three production tasks were administered to children. A repetition task was used to examine children's production of the plural marker in plural noun phrases, and 2 Berko-style tasks evaluated children's production of the plural marker in bare nouns. Behavior on these tasks was compared with plural marker comprehension for each individual child. Results: There was a correlation between children's comprehension of the plural marker and their production of the plural marker on plural noun phrases in the repetition task but not between comprehension and production of the plural marker on bare nouns in the Berko-style tasks. Conclusions: Assessments of plural morphology as a clinical marker of language impairment in Spanish-speaking children may be problematic, especially in children acquiring dialects of Spanish with /s/ lenition, such as those originating in Chile, the Dominican Republic, Cuba, Puerto Rico, and Central America. Instead, for children acquiring /s/-leniting dialects of Spanish, assessments of the plural marker in noun phrases produced within a sentence frame may be a better indicator of acquisition than traditional Berko-style tasks that elicit bare nouns.