We investigated toddlers' understanding of the hierarchical syntactic configurations that constrain the referential meanings of reflexives and pronouns. In particular, reflexives must co-refer with the c-commanding antecedent within the local domain (Principle A) (e.g., He[subscript i] washes himself[subscript i]. John[subscript i] knows that Bill[subscript j] likes himself[subscript j].), and pronoun reference must be disjoint from its local c-commanding antecedent (Principle B) (e.g., He[subscript i] washes him[subscript j]. John[subscript i] knows that Bill[subscript j] likes him[subscript i].). French-learning 30-month-olds participated in an eye-tracker task. In Experiment 1 each trial presented a simple sentence containing a reflexive or a pronoun and a target verb (e.g., "Il[subscript i]se[subscript i]/le[subscript j]lave." "he[subscript i] washes himself[subscript i]/him[subscript j]"), while displaying side-by-side pictures depicting self- directed versus other-directed actions of the target verb. Experiment 2 tested the locality conditions of the principles using complex sentences, with the target verb and the reflexive/pronoun appearing in the embedded clause (e.g., "Le bébé[subscript i] voit que le papa[subscript j] se[subscript j]/le[subscript i] lave." "The baby[subscript i] sees that the dadj washes himself[subscript j]/him[subscript i]"); the pictures were those of Experiment 1, with the patient of the verb being the local antecedent in the embedded clause versus the non-local antecedent in the matrix-clause. Experiment 3 tested the c-commanding requirements of the principles with sentences containing a complex subject, a reflexive/pronoun and a target verb (e.g., "Le bébé[subscript i] du papa[subscript j] se[subscript i]/le[subscript j] lave." "The baby[subscript i] of the dad[subscript j] washes himself[subscript i]/him[subscript j]"). In the pictures the patient was the linearly farther versus closer antecedent. Eye-gazes to action images showed adult-like interpretations across sentential structures, demonstrating that binding principles are in child grammar during age two.