This study explored the perspectives of the representatives of teacher unions and school principals in the process of promotion of educators. The study aimed at highlighting how the representatives of teacher unions and principals understand their role in the promotion interview process, the challenges experienced and the factors they considered when recommending educators for promotion. This qualitative case study focused on one district in Mpumalanga Province. Data were generated through semi-structured interviews with two representatives of a teacher union and three school principals. The representatives of the teacher union comprised a branch secretary and a site steward. This study found that the principals performed their role in promotion interviews as stipulated in the Employment of Educators’ Act of 1998; however, they were skeptical about the activities of the union representatives who are tasked with the prescribed role of observer. Representatives of the teacher union felt that their role extended beyond that of passive observer during the promotion interview. There was evidence of lack of trust and a power struggle between the principals and the representatives of the teacher union which affected their relationship during and after the interview process. While the principals appeared capable of managing the interviews, the activities of the union representatives shaped the process and the outcome of the selection process. This study also found that although all participants mentioned academic qualifications, subject specialization, good communication skills, sound human relations and managerial skills as factors to consider when recommending teachers for promotion, possible nepotism threatened fair procedures during the promotion interview process.