For most of the twentieth century, South Africa was the world’s largest producer of gold. Although the country enjoyed a reputation for leading the world in occupational health legislation, the mining companies developed a system of medical surveillance and workers’ compensation which compromised the health of black gold miners, facilitated the spread of tuberculosis, and ravaged the communities and economies of labour-sending states. The culmination of two decades of meticulous archival research, this book exposes the making, contesting, and unravelling of the companies’ capacity to shape – and corrupt – medical knowledge.