This book presents a thorough description of morphosyntactic knowledge developed by learners of French in four different learning situations — first language (L1) acquisition, second (L2) language acquisition, bilingualism, and acquisition by children with Specific Language Impairment — within the theoretical framework of generative grammar. This approach allows for multiple comparisons across acquisition contexts, which provides the reader with invaluable insights into the nature of the acquisition process. The book is divided into four parts each dealing with a major morphosyntactic domain of acquisition: the verbal domain, the pronominal domain, the nominal domain, and the CP domain. Each part contains four chapters, the first one presenting an overview of the basic facts and analyses of the relevant properties of French, and the next three focusing on the different acquisition contexts.