This paper discusses the online Personal Learning Planner (PLP) project underway at the National Institute for Community Innovations (NICI) and presents some of the details of the theory and thinking that is guiding its development. The World Wide Web-based software is part of work by NICI to develop tools for enhancing preservice teacher education and supporting increased use of technology, especially in professional development schools. The PLP is designed to assist learners through the processes of: self-assessment of strengths, interests, and aspirations; planning preservice education learning goals and projects; linking goals and projects to valued outcome standards; creating original work and sharing the work with others; receiving high quality feedback for the improvement of work; documenting and validating the achievement of learning goals; and assisting in the selection and preparation of exhibits of learning. The following basic assumptions guide the thinking behind the PLP: face-to-face as a foundation of learning; three bases for planning and action for learning (institutional, professional, and personal priorities); the learning cycle; focus on the learner's work; self-direction and making meaning; and flexible thinking tools. (Contains 14 references.) (MES)