This study was an attempt to investigate the developmental rate of fluency, accuracy and complexity among 12 EFL learners within the framework of chaos complexity theory. To carry out this study, 6 female and 6 male participants in two levels of proficiency (pre-and upper-intermediate) were put in two classes taught by the same teacher and following the same course. Every two months (for a period of four months) they were asked to write a narrative using the pictorial sequence of a story, and they were also asked to tell the same story orally after three days. Their productions were analyzed for fluency, accuracy and complexity (lexical and grammatical). The results, compared inter and inrta-individually, revealed that there was no common pattern of development among different learners with different proficiency or gender. A closer examination of the oral and written productions of these learners showed that the emergence of complexity, fluency, and accuracy could be seen as a system adapting to a changing context, in which the language resources of each individual were uniquely transformed through use and in which chaos, dynamicity, unpredictability, and self-organization were clearly observed in the participants’ productions.
