Sustainable Development Goal No. 4 (SDG4) resonates with all education systems of the world. It has resulted in education policies being created and promulgated with sustainability and development in mind. In the context of the Fourth Industrial Revolution (4IR), sustainability speaks to the need for schooling systems to operate as a knowledge society and to maximally exploit the abundance of knowledge assets that exist in their ecologies. This implies that they must adopt knowledge management (KM) to take advantage of the 4IR era aligned technological innovations, instructional practices and administrative standards. In light of the view that, of all KM processes, knowledge sharing reigns supreme and gives rise to the generation of new organisational knowledge as well as the innovation of existing organisational knowledge; the study adopted a qualitative approach embedded in an interpretivist paradigm to explore the perceptions of teaching and support staff- specifically six teachers and four administrative clerks (altogether ten participants) - of factors contributing to unequal power relations in knowledge sharing practices at two selected schools in Nkangala Education District, Mpumalanga Province (South Africa). The study found that poor leadership practices contributed to unhealthy professional interactions, knowledge hoarding, contravention of contextual ethics (of Ubuntu), trust deficit, top-down communication and workplace bullying.