Full text article.This study examined teachers' experiences with and views on professional development programs for improving science and mathematics teaching in secondary schools in Tanzania. The study employed a qualitative research approach using descriptive case study design and employing mainly interview as a data collection method. The study involved 42 participants selected from Dodoma Municipality in Dodoma Region, Tanzania. The findings of the study revealed that workshops, seminars, upgrading through long courses, peer coaching, collaborations and panel marking of students' examinations are programs that promote professional development for science and mathematics teachers. Additionally, teachers had low accessibility to the professional development programs. Furthermore, the findings indicated that inter-school subject associations, peer collaboration and the use of technology are major strategies to improve professional development opportunities for teachers. Similarly, PDPs have a positive impact on teachers' performance. The study recommended that professional development opportunities should be improved so as to provide opportunities for teachers to participate frequently in various PDPs.