Complexity, accuracy and fluency: Definitions, measurement and research

Investigating complexity, accuracy and fluency in L2 is a fascinating, but daunt- ing, task: fascinating, because it addresses fundamental issues in language acquisi- tion and language use and how they are affected by varying conditions; daunting, because of the complex, multidimensional nature of CAF, the interacting effects of both learner-internal and learner-external factors, and the multiple challenges which these present. The chapters in this volume illustrate not only the produc- tivity but also the diversity of current research on CAF, diversity in terms of issues investigated, theoretical orientations and methodological approaches. The
heterogeneity of topics and methodology, however, does not contradict the homo- geneity of purpose, which is to contribute to a fuller understanding of L2 knowledge, use and development.