The restitution of land to the Khomani San "bushmen" and Mier "agricultural" communities in May 2002 marked a significant shift in conservation in the Kgalagadi area in South Africa. The Khomani San and Mier communities were awarded land inside and outside the Kgalagadi Transfrontier Park. Given that the Khomani San interact more with nature, biodiversity conservation will only benefit from the land restitution in this case if the Khomani San are good environmental stewards. Therefore, this paper uses the contingent valuation method to investigate the values assigned to biodiversity conserved under the various forms of land tenure arrangements by the Khomani San in the Kgalagadi area and compares them to similar valuations by the adjacent Mier community. The proposed conservation programme sought to plant as many native trees, shrubs and grasslands as required to reduce biodiversity loss by 10% in terms of the quantities of each of the selected major species of the area. Despite the fact that the conservation programme has both winners and losers when implemented under any of the three land tenure arrangements considered, the findings suggest that the Khomani San, whose attitudes towards modern conservation have not been evaluated until now, and the adjacent Mier community generally attach a significant economic value to biodiversity in their area. The net economic value for conserving biodiversity under the various forms of land tenure arrangements by the Khomani San ranged from R928 to R4 672 relative to the Mier community’s range of R25 600 to R64 000. However, for both communities, in order for all members of the local communities to support biodiversity conservation unconditionally, mechanisms for fair distribution of the associated costs and benefits should be put in place.