This study aims to increase understanding of the values and outcomes of teacher action research in conservatoire education. Teacher action research has been found to stimulate both professional development and improvement of teaching practice. A multiple-case study design was employed to examine teachers' activities and their perceptions of the value of action research. Findings from the cross-case analysis include teachers' perceptions of action research as a way to stimulate the advancement of both their teaching practice and their professional development. Constructive collaborations and self-reflections related to teacher action research were found to reinforce their learning and teaching.