In this paper, I critically examine my role as a mentor to a group of mid-career mathematics teachers, to better understand how mentoring practices influence teacher learning. The teachers taught mathematics to Grades 5 or 6. They planned and taught lessons to promote conceptual understanding of mathematics through the use of discussions, and reflected on their own and pupils' learning in the process. The study lasted for a year. It draws on qualitative data from sources such as semi-structured interviews, participant observation, and teachers' reflective journals. As a mentor/researcher I found that in the case of mentees' perception of the mentor as a problem solver or evaluator of performance learning was inhibited, whereas mentor and mentee relationships established on mutual trust supported mentees' personal and professional growth. The close work with the teachers also gave me insights into aspects of learning influenced by teachers' beliefs and understanding of mathematics and of how learning takes place. The study has implications for other such teacher education initiatives, particularly in the context of developing countries like Pakistan.