Chapter 6, Enhancing Professional Knowledge through Mentoring, explores the roles of mentoring in contributing to novice ESL teachers’ professional knowledge in their first years of teaching. Based on the four case studies, the authors present a comprehensive discussion on how mentoring bridges the gap between teacher education programme and the real classroom, expands teachers’ knowledge base, and reinforces teachers’ curricular knowledge. Drawing on Furnished Imagination by Kiely and Askham (2012) as the theoretical underpinning of the case studies, the authors detail how the novice ESL teachers combine their sense of self and their sense of possibility with the input gained from a mentoring programme, which enable them to enhance professional knowledge. Additionally, this chapter addresses the social and contextual dimensions of mentoring pertaining to its roles in contributing to teachers’ professional knowledge.