To help produce more expert coaches at the participation and performance levels, a number of governing bodies have established coach mentoring systems. In light of this trend, against the limited literature on coach mentoring and the risks of superficial treatment by coach education systems, this article critically discusses the role of the mentor in coach development, the nature of the mentor-mentee relationship, and, most specifically, how expertise in the mentee may best be developed. If mentors are to be effective in developing expert coaches, we consequently argue that a focus on personal epistemology is required. On this basis, we present a framework that conceptualizes mentee development on this level through a step by step progression, rather than through an unrealistic and unachievable leap toward expertise. Finally, we consider the resulting implications for practice and research with respect to one-on-one mentoring, communities of practice, and formal coach education.