The chapter presents a study of the relation between the comprehension and production of articles and subject clitic pronouns in 2-year-old Frenchacquiring children. The production of grammatical morphemes occurring in the spontaneous speech of ten children was related to the performance these same children obtained in a comprehension task testing the children's understanding of the grammatical morphemes in question. Success in the task required children to retrieve the meaning of homophonous or nonce words on the sole basis of the category-specific grammatical morpheme preceding them-a definite article for nouns and a third person subject clitic pronoun for verbs. Overall, results indicate that comprehension and production are closely related. For the majority of the children, a high level of comprehension corresponded to a high level in production. The profile of one participant, and to a lesser degree that of two others, suggests that production might be ahead of comprehension. It should be noted, however, that in this study comprehension could not be assessed with the same degree of detail as spontaneous production. To shed further light on this issue, future studies should find a way to assess children's comprehension in finer detail, include additional participants, as well as plan studies where both production and comprehension are assessed on a longitudinal basis. Moreover, in order to better evaluate what children have acquired and how they have acquired it, it is suggested that studies of early language acquisition should include both comprehension and production as a standard method of analysis.