This volume presents a state-of-the-art descriptive and explanatory analysis of the second language development of Romance tense-aspect systems. It contains new experimental data from adult French, Catalan, Portuguese learners, and Italian children learners. Standing research questions are addressed and pedagogical implications for foreign language classrooms are proposed arguing that there are possible commonalities in the instructional sequences of tense-aspect development in Romance languages. The first chapter presents an overview of current theoretical approaches and a summary of empirical findings. The following four chapters introduce new empirical data from a variety of theoretical perspectives (e.g., the Aspect Hypothesis, the UG/Minimalist framework). Chapter 5 proposes practical pedagogical approaches for the foreign language classroom based on empirical findings. The last chapter summarizes and discusses these findings in order to start elaborating a more comprehensive model of the development of tense-aspect marking in the Romance languages.