This working paper proposes an integrated Nature-based Solutions and Project Management (NbS-PMI) framework for the design and delivery of Earthship construction projects in sub-Saharan Africa. Earthships — self-sufficient buildings constructed from recycled tires, glass bottles, aluminium cans, and adobe — are argued to constitute a form of NbS exceptionally well-suited to the African urban context, given the region's abundant waste streams, high solar irradiance, water scarcity, and available labor. The paper develops a four-phase implementation framework (Site Assessment, Design, Implementation, and Monitoring) grounded in PMI project management discipline and validated against an original community center project proposal and two international case studies. A 12-indicator monitoring framework maps project outcomes to SDG targets 6, 7, 8, 11, 12, and 13. The central argument is that project management discipline is the critical missing link between NbS policy ambition and on-the-ground delivery in African cities.