This study aimed to explore barriers to implementing peace education in secondary schools in South Africa. The empirical inquiry employed qualitative research methodology and evaluation research design to examine the implementation of a peace education programme in three selected secondary schools in the Western Cape, South Africa. Purposive sampling was used to select the research sites and participants. Data were collected through semi-structured individual interviews with the manager of the Quaker Peace Centre (QPC) programme and school principals; and focus group discussions with teachers and learners. The data were analysed through thematic content analysis. Findings indicate that peace education was implemented with modest success outside the formal curriculum by following a multimedia approach using learner-run peace clubs and anti-bullying campaigns. However, barriers to the implementation of peace education persist, including financial constraints; inadequate allocation of time to peace education; poor parental involvement; overburdened teachers; and negative attitudes and societal influences. Based on these findings, the study recommends that government and school management should support the successful implementation of peace education by providing teacher training on peace education, including peace education in the mainstream curriculum; ensuring that all stakeholders participate in peace education efforts; and prioritising funding for implementation.