Sound research in Computer-Assisted Language Learning (CALL) necessarily draws upon established second language acquisition (SLA) constructs and approaches in exploring learner-computer and learner-learner interaction. At the same time, CALL research has the potential to shape (and also complicate) aspects of SLA theory. Indeed, the digital medium affords CALL researchers certain advantages; however, it also presents a host of methodological challenges. Among these challenges, sufficiently tracking learner behavior seems to be critical.