The purpose of this intrinsic case study was to examine how preservice music teachers' participation in a 4-year lab choir setting contributed to their teacher identity construction. This lab choir represents an uncommon case of peer teaching because preservice teachers enroll in the course each semester of their undergraduate career and participate as singers for multiple semesters before taking on the teacher role, at which point they are teaching an ensemble made up largely of younger students. The eight participants in this study were choral music education majors who had been members of the lab choir since their first semester at the university. Three themes emerged from the data: "culture of identity construction", "evolution through coursework", and "peers as future selves." Participants felt the lab choir experience contributed positively to their identity construction and skill acquisition. Implications for music teacher education are discussed.