Purchase of development right (PDR) programs pay landowners to protect critical lands through legal agreements, or conservation easements, between a landowner and a land trust or government agency. These agreements permanently limit land use to protect its conservation value. Under conservation easements, landowners continue to own and use the land and can sell it or pass it on to heirs. Easements can be sold to government agencies, nonprofit organizations, or private corporations or donated to a land trust or government agency. PDR programs can be funded through bonds, federal programs, or tax revenues.