Reflective teachers are always searching for ways to improve their teaching. When this reflection becomes intentional and systematic, they are engaging in teacher research. This type of research, sometimes called "action research", can help bridge the gap between theory and practice by addressing topics that are relevant to practicing teachers. This article synthesizes literature within music education and general education to address (a) the conceptual underpinnings of action research, (b) characteristics of action research and teacher research, (c) action research critiques, and (d) implications for teacher research as a form of professional development.