As the role of computer-assisted instruction (CAI) rapidly expands in the educational and training efforts of all types of organizations, the need for well-designed, learner-centered CAI continues to grow. The CAI design principles and methodology proposed herein provide systems designers with a framework for designing effective, learner-centered CAI systems that support learning with information technologies. Implementing the framework should lead to CAI that better supports learners in the development of their mental schemas, and ultimately, in achieving their learning objectives.