The Square Kilometre Array (SKA) is one of the largest and most ambitious research infrastructure ever to be built. South Africa will be hosting one of its two main sites. The decision to host such an ambitious project for a middle-income country required careful consideration of the potential benefits and the associated risks for the socio-economic development of the country and the region more broadly. This working paper describes how the potential impact of SKA for South Africa was envisaged from the start of the project, how this was integrated in the project development, what policy initiatives and interventions were taken to maximize impact and the lessons learned, from South Africa’s science policy perspective, during the early phases of the development of the SKA.