The purpose of this study was to understand the impact of the Visiting Teacher (VT) Mathematics secondary program by inquiring into the pedagogical approaches of selected teachers in Karachi. Furthermore, the challenges they encountered during the implementation of the new instructional strategies in the classrooms were studied. The field work was undertaken in three of Aga Khan University, Institute for Educational Development (AKUIED)' s co-operating schools, from which two male and one female VTs had attended the program in 1998. The data was gathered from VTs, headteachers (HTs), colleagues, students, and course tutors through interviews, observation and documents within a qualitative paradigm. The major findings of the study were that the VT program in Mathematics (secondary) had impacted on VTs to at least some extent, resulting in increased student participation in the classroom. The VT program also contributed to the raising of awareness about the subject of Mathematics and the teaching and learning processes associated with it. This study revealed that prior to joining the program VTs had a lack of conceptual understanding of the subject matter, as well as a lack of awareness of new pedagogical approaches. After the program it was generally found that the teachers were employing new pedagogical approaches. These were found by them to be useful in order to enhance understanding of the concepts to be taught by relating them to life experiences. The program also helped the teachers to develop thinking skills and taught them to place an emphasis on meaningful learning. They developed reflective practice and had enhanced their course content knowledge but punishing students was found to be a common practice. An important finding was that VTs had made a major shift in their perception of teaching and learning and moved from a traditional mode of teaching towards progressive instructional approaches. Challenges faced by VTs in the implementation of new approaches were discussed. In order to improve the program, some recommendations have been proposed.