The purpose of this interview study, conducted with 12 primary music teachers in Singapore, was to determine whether peer observation is viewed as a learning approach that may contribute to professional growth. We found that both specialist and generalist music teachers highly valued peer observation and were optimistic about the use of video-mediated peer observation. As a form of professional development, peer observation appears to enhance understanding and application of teaching strategies, allows teachers to anticipate students' reactions during lessons, and builds their confidence as instructors. Video-mediated peer observation, which is both convenient and easily accessible, provides contextualized examples of effective classroom practices. We conclude that peer observation activities are most meaningful and transformative when they are responsive, that is, designed with music teachers' voices and professional development needs in mind.