Stephen’s research activities centre upon opera and conducting, with a focus from the mid-eighteenth century until the present day. Interests include the history of opera and the rise of the conductor, along with performance practice-based research across both areas; the developing role of the conductor from the late nineteenth century; Richard Wagner; Mozart reception; Gustav Mahler as conductor and opera practitioner; the impact of historically aware performance practice upon the conducting profession; aspects of authenticity, Werktreue and Retuschen; the historical background to the conducted repertoire are all central areas of teaching and research. His teaching of conducting incorporates the study of the marked scores of iconic conductors of the past. The collection and study of such material forms the core of his current research.