Considering the promising potential of ICALL and intelligent feedback, this paper addresses this topic from the perspective of practical applications. It reviews existing intelligent language learning systems and their feedback capabilities, arguing that while ICALL is very promising and highly complex, its development should be more principled. In other words, the decisions behind the system design need to be justified theoretically, integrating technology with theory, research, and practice in instructed SLA. To support this argument, this paper provides an example of how this was achieved in the context of L2 graduate academic writing. It describes a new natural language processing-based application, IADE (Intelligent Academic Discourse Evaluator), explaining how pedagogical and theoretical perspectives were synthesized, moving from practice to theory and from theory to design. Empirical findings on the provision of feedback and project-specific discourse analysis research also informed the development of IADE so that it meets the particular needs of the targeted learners. From the technological point of view, the program’s overall conceptualization and operationalization draw from the principles of Evidence Centered Design. Since development generally leads to implementation, the paper concludes with issues related to ICALL evaluation.