At the core of the professional development school movement is the assumption that teachers' voices must be welcomed in the wider educational community through participation in mutual collaborative inquiry with university faculty. However, little thought has been given to the nature of teachers' voices, the dilemmas that arise when those voices are heard in the context of educational reform, and whether, by bringing teachers' voices into the educational hierarchy, the education of children will improve. This paper argues that the welcoming of teachers' voices is more complex than simply providing occasions for teachers to speak and that, without thoughtful consideration of this issue, efforts aimed at advancing the rights of teachers to a voice in reform proceedings may be undermined. The concept of voice is expanded using three perspectives: voice as personal/private development, representative action, and collectively critical. These metaphors are used to analyze the realities and dilemmas of voice in the professional development school context. It is concluded that active participation in collaborative work in professional development schools requires balanced use of voice from all three perspectives. Structured conversations were held with two collaborative groups, one from a high school and one from a middle school, to gather data for this study. (Author/IAH)