African cities face critical challenges in delivering essential services due to limited financial re-sources and vulnerabilities to climate change impacts, such as floods and water and energy in-security. Many cities lack adequate stormwater drainage infrastructure and capacity, hindering their ability to implement environmental sustainability projects. Reports show that two-thirds of sub-Saharan African cities are "at extreme risk" from climate change, threatening local infra-structure and development. Climate change mitigation and adaptation require integration across all sectors, as development without environmental considerations can exacerbate vulnerabilities. This study evaluated how selected African cities have incorporated environmental sustainability into their development plans, using the OECD mainstreaming framework for assessment. The research employed a qualitative approach through thematic content analysis, examining both successes and challenges in mainstreaming environmental sustainability. Findings indicate var-ying success levels, with some cities excelling in integrating certain environmental sustainability dimensions, while others face significant barriers. The study identifies key enablers and im-pediments to effective incorporation of environmental sustainability into urban development, concluding that while some aspects of environmental sustainability mainstreaming are well ad-dressed, others remain inadequately integrated. These findings underscore the need for a more systematic and comprehensive approach to embedding environmental sustainability within ur-ban development policies and practices across African cities.