This study combines Walter Mignolo's decolonial thinking with Carol Bacchi's 'what's the problem represented to be' approach to analyse how sustainable development is problematised in Tanzanian education policies. We find a dominant problematisation of sustainable development that sees it as a problem of economic competition, further nested in a lack of human resources. We link this problematisation to a national development discourse that became dominant through key turning points following the liberalisation of the Tanzanian economy in the 1980s. It is based on assumptions from Western epistemologies and human capital theory, where knowledge becomes a narrow concept while economic growth is seen as a prerequisite for sustainability. This excludes other epistemologies, such as indigenous knowledge. From a decolonial perspective, this leads to a concept framed within the rhetoric of modernity. We explore a decolonial option to this discourse that originates from Julius Nyerere's principles of Education for Self-Reliance.