This article discusses a university-public school partnership involving 10 school sites, which have become professional development schools (PDSs). These PDSs contribute to a continuum of professional development for educators at all levels: preservice teachers, inservice teachers, public school administrators, and teacher educators. Professional development schools provide opportunities to redefine roles and relationships between and among preservice teachers, inservice teachers, college faculty, and elementary and secondary students. Three strategies, which have made important contributions to successful efforts to implement collaborative professional development at the sites, are outlined: engaging in inquiry, building a team spirit, and mutual critique. A collaborative strategy and structure for inquiry that was implemented is described: a team consisting of preservice teachers, inservice teachers, and college faculty worked together to build the language arts and social studies methods course curriculum in ways that link the elementary school curriculum to the college curriculum. Examples of the following program features and efforts are also outlined: building a team spirit in the college classroom, planning and debriefing time for cooperating teachers and their preservice students; and professor-researchers becoming learners in their own classrooms. (IAH)