Literature we reviewed indicated that, during the formulation of the re-entry policy in Zambia, teacher unions; Zambia National Union of Teachers (ZNUT) and Secondary School Teachers Union of Zambia (SESTUZ), were involved. However, literature remained unclear on how the two unions were involved in the process. Based on this ground, we conducted this study to establish how the teacher unions were involved in the formulation of the re-entry policy in Zambia. In this study we adopted three major dimensions of the research process ontology, epistemology and axiology. We employed used a qualitative case study design. The study was done in Zambia on a sample drawn from schools, zones, districts and provinces which conveniently sampled. The study population consisted of people 20 Teacher Union Representatives drawn from Zambia National Union of Teachers (ZNUT) and Secondary School Teachers Union of Zambia (SESTUZ) and directors drawn from the Ministry of General Education (MoGE) Department respectively. This study employed the recommendations of both Creswell (1998) and Morse (1994) to determine the sample size. We sampled of 26 participants. However, due to saturation, only11 union representatives and 4 directors were interviewed. Data was collected from all participants using interviews guides. Thematic analysis was used to analyse the data. The study was ethically cleared with the University of Zambia Directorate of Research and Graduate Studies. The study found that Teacher unions, such as ZNUT and SESTUZ, were actively involved in the formulation of the re-entry policy, participating in consultations, advocacy, lobbying, support for implementation, and monitoring and evaluation of the policy. Their involvement was crucial in shaping the policy and ensuring it is responsive to the needs of girls who dropped out of school. Their contributions included advocating for the rights of teachers and learners, supporting policy implementation, and providing input during the formulation process. The study highlights the importance of involving teacher unions in education policy formulation and implementation, as their input is essential for policies to be effective, practical, and inclusive, benefiting teachers, students, and the education system as a whole.