This book presents an empirical study on the acquisition of aspect by second language learners of French. Kevin McManus provides a critical assessment of previous research on the acquisition of aspect, turning both to conceptual and empirical work. As a consequence, this book sheds new light on the long-standing question of the contribution of a learner's first language (L1) on their acquisition of a second. Alongside the role of the L1, language universals are also addressed in this study, in which the claims of the Aspect Hypothesis are carefully examined. Data are collected from 75 English- and German-speaking university learners of French. Participants undertook three tasks: two production tasks and a sentence interpretation task. The results show that L1 form-meaning pairings for aspect significantly influence acquisition at the early stages of development. However, as proficiency increases L1 influence begins to recede. Prototypical effects appear to increase with proficiency, contrary to the Aspect Hypothesis.