This chapter presents the results of a study on interlanguage variation. The production of four L2 learners of Italian, tested four times at yearly intervals while engaged in four oral tasks, is compared to that of two native speakers, and analysed with quantitative CAF measures. Thus, time, task type, nativeness, as well as group vs. individual scores are the independent variables and complexity, accuracy, and fluency are the dependent ones. Results show how both L2 learners and native speakers display situational variation, but with clear differences amongst the two groups. Longitudinally, all L2 learners achieve some progress, even if manner and rate change from task to task and from learner to learner. The discussion of results provides some stimulating points to be addressed in future research. (Contains 6 tables and 5 footnotes.) [For complete volume, see ED539539.]