Compulsory acquisition of land by the state for public purposes is an entrenched feature of national constitutions. Yet the scope of private property is rarely defined. This is problematic in agrarian economies where millions own land under non-statutory arrangements that were historically excluded from recognition as property. This study examines the case in Africa where more than 650 million people are untitled customary landowners. Despite vibrant constitutional change, protection of these rights remains disappointing, while the grounds for taking land have expanded. However, this article concludes that reining in the scope of public purpose is not the most useful way forward. It would be more productive to persist in bringing constitutional force to bear on the standing of customary rights, along with democratizing procedures towards full community participation in deciding how public purpose acquisitions should proceed. The result would be greater tenure security, good governance and more peaceful relations between the state and people regarding land.