This project will hold a series of workshops focused on fostering interdisciplinarity in the study of second language acquisition. The workshops will be jointly organised by Lancaster University and the University of Cambridge in the UK and by Kobe University and Tokyo University of Foreign Studies in Japan. Language learning is a socially, culturally and economically important activity. In itself it represents a significant industry - the UK language teaching industry alone was estimated to be worth £17.5 billion to the UK economy in 2011 - the global market in 2017 was worth $6.3 trillion US dollars. Yet language learning, and the study of how to understand and promote it, is a very challenging and complex process to investigate. It is engaged with from different perspectives by many disciplines, including psychology, linguistics and neuroscience, all of which bring relevant perspectives to bear on the investigation. This means that the study of second language acquisition is both intrinsically and procedurally complex. It is intrinsically complex given that the object of inquiry itself - language - is exceptionally complex. That complexity is compounded by i.) the necessity to acquire different domains of language use to form a fully functioning system of usage and ii.) individual learner characteristics such as native language, type of instruction, and motivation. Yet while the investigation of a complex phenomenon like language acquisition can significantly benefit from insights, tools, and methods from many disciplines, it is still relatively rare to find studies that combine multiple approaches. In part that is undoubtedly because it is procedurally difficult - coordinating an approach to the study of second language acquisition across a range of disciplines is so complex that until recently this has not been done systematically or at notable scale. In addition, we believe that minimal exchange between relevant disciplines has contributed to this issue. In this context it is unsurprising to note that the conceptual and empirical progress that has been achieved in second language acquisition research has been fuelled by an increasing range of methods and approaches from a range of disciplines. For example, experimental approaches, arising from psychology, using artificial or natural languages, have made it possible to investigate how changes across exposure conditions such as input frequency, instruction type, or prior knowledge affect learning in rigorously controlled environments. From linguistics, the construction of learner corpora, large bodies of attested learner language, are growing in size and task types covered, with increasingly rich annotation supporting detailed analyses employing sophisticated statistical methods. These are now being deployed in combination with other methods, including EEG experiments. What we need to do now is to better integrate such innovations to capitalise upon studies which are showing such promise by doing so. This grant will allow researchers working in corpus linguistics, psycholinguistics and second language research in two countries to come together to realise the benefit that better interdisciplinary working can bring to the study of second language acquisition. In doing so the researchers will outline a road map of potential work on second language acquisition that should happen in this interdisciplinary space, outline the relevant current context in the UK and Japan and identify gaps and opportunities that, if engaged with, would materially improve our understanding of how second languages are learned. The meetings that this grant will fund will allow the researchers to both plan out a world-leading research agenda that might be funded by a future UK/Japan joint research funding call and to facilitate the networking that is a necessary precondition to allow the best teams to be constructed to deliver that research agenda.