This paper reports findings from a year-long self-study of the development of a music teacher-research group. Analysis of transcripts of audio-recorded talk from group meetings, and individual interviews with group members demonstrates that in spite of obstacles encountered in the process of conducting collaborative work, university educators and elementary music teachers involved described outcomes of the group's work as mutually beneficial. We propose that a teacher-research group involving university educators and K-12 teachers in music education is one form of "professional learning community" (Feiman-Nemser, 2001) that may be used to mentor early career music teachers. More than a "support" group, a teacher-research group designed to develop members' understanding of and abilities to conduct action research will foster professional skills in asking critical questions of classroom practice and seeking evidence-based answers. For teacherresearch groups to contribute to the professional development of music teachers, however, we suggest that they be developed over a substantial period of time, and use a structured framework with specific goals for group members. Ideally, to be sustained and developed over time, such groups would be funded.