On Complex Dynamic Systems Theory and second language development: Looking back at over two decades of theory and research

In celebrating over two decades of the integration of Complex Dynamic Systems Theory (CDST) in the study of language learning and development, this paper looks back at some cornerstone publications that marked certain milestones in a quarter century of historical trails this theory has made in the field of second language development research. This paper then reviews two of the main tenets of this theory that feature frequently in CDST-inspired studies and discusses their contributions to advancing our understanding of language learning and development over time. This paper also mentions some concerns voiced in the systematic criticisms on the current practice of applying this theory in researching language learning phenomena and concludes by pondering potential directions moving forward.