My experience as a learner and later on as a teacher and teacher educator in a rural area, and exposures to teacher education programmes in urban areas made me realise that there is a wide spread belief amongst learners, teachers, and teacher educators that mathematics is like a bag of tools (Ernest, 1994) which is made up of predetermined facts, rules and principles. It is also believed that mathematics is based on universal and absolute foundations, and the learning of mathematics should involve the rules, facts and principles as the basic ‘’building blocks’’ (Thompson, 1992) of mathematical knowledge. However, my experience as a student of the current M.Ed. programme at the Institute for Educational Development (IED) of the Aga Khan University portrayed a totally different picture of mathematics; mathematics is a continually expanding field of human creation and invention, and learning mathematics occurs’’ inside learners' heads’’ (Anderson & Reynolds, 1995) as a result of the active efforts to make meanings of mathematical concepts. The ultimate purpose of this study was to try to investigate how teachers' beliefs influence their classroom practices, and what impact they have on teachers' own professional growth` and students' learning of mathematics. This study was conducted in one of the cooperative schools of the IED. The sample for this study included two primary mathematics teachers; one, who had been teaching mathematics for seven years, had attended an eight-week Visiting Teacher Programme at the IED. The other one, who had been teaching for one year only, had no pre- or in-service training. The field work lasted for six weeks during which I used an integrated repertoire of qualitative research instruments such as semi-structured interviews, non-participant observations, pre- and post-lesson conferences, checklists, teachers' reflective stories and some documentary evidences maintained by the teachers. I also closely examined the students' understanding of certain mathematical concepts presented by the teachers during their classroom teaching. The data was analysed as two separate case studies which present detailed biographical data about the two teachers, their theoretical frameworks (stated beliefs), and actual classroom practices (enacted beliefs) with my own interpretation and analysis. The synthesis of the study uncovers a number of issues emerging from the analysis of the findings that may interest other mathematics teachers, teacher educators, teacher education programmes, and research in education in general.