In many universities offering qualifications in education, Paulo Freire's critical pedagogy features prominently in curricula for pre-service teachers of English. Student teachers are prepared with the knowledge and skills that enable them to use approaches from critical pedagogy to teach English effectively in their classrooms upon graduation. Critical pedagogy affords pre-service teachers of English training in teaching critical literacy, a pedagogy of self-empowerment, and tools for teaching critical thinking. However, student teachers may not easily exploit these affordances when they start to teach since many constraints in the school system may impede the effective implementation of critical pedagogy in the English classroom. These constraints include the inflexible Annual Teaching Plan, the practice of teaching for assessment, and contradictions in the Curriculum and Assessment Policy Statement (CAPS). As a result, there is a disparity between the vision of teaching English in critical ways on the one hand and opportunities to realise this vision within the structures of South African policy on the other. In this article, we explore this disparity and its implications for learning to teach English within a critical pedagogy framework.