This study used an eclectic multiple-case design to explore what drives three large-scale mining companies' involvement in CSR-mediated development activities, and their philosophical underpinning. The research discovered that although there were nuances between cases in the order in which they rated the strength of 11 potential drivers of CSR, eight of them were important. Three (3) of these were strong drivers -reputation management, pre-emptive anti-regulationism, and pre-existence of local development plans. Five others were moderately strong drivers. The investigations further found that the philosophical underpinnings of the case companies' CSR were based on 'Common-Sense Morality,' a duty-based deontological moral philosophy that is a departure from widely held instrumental positions associated with Egoism. It also identified constrained profitmaximization as the CSR strategy from which their CSR policies emanated.