Teacher leadership is generally accepted as having a critical role in supporting school improvement. However, most knowledge on teacher leadership comes from the West, the roles of teacher leadership in the East, particularly, the most populated country, China, remain largely unexplored. Shanghai students were ranked top in PISA 2009 and PISA 2012 and these successful experiences have set examples to the world. This paper aims to report why and how Shanghai schools have been successful from the perspective of teacher leadership. A qualitative study to explore the roles of teacher leadership in six Shanghai schools was conducted. The findings confirmed the critical contribution of teacher leadership with three specific roles of teacher leadership emerging from leadership practices to support school improvement. The findings from this study may contribute to the literature on how teacher leadership sustains school improvement. [For the complete Volume 15 proceedings, see ED574185.]