Under the Mexican government, some indigenous people had land rights under ejido and agrarian communities. Under ejidos, indigenous communities have usufruct rights of the land. Indigenous communities choose to do this when they do not have the legal evidence to claim the land. In 1992, shifts were made to the economic structure and ejidos could now be partitioned and sold. For this to happen, the PROCEDE program was established. The PROCEDE program surveyed, mapped, and verified the ejido lands. This privatization of land undermined the economic base of the indigenous communities much like the taking of their land during colonization.