The Williamson Act, also known as the California Land Conservation Act of 1965, enables local governments to enter into contracts with private landowners for the purpose of restricting specific parcels of land to agricultural or related open space use.  In return, landowners receive property tax assessments which are much lower than normal because they are based upon farming and open space uses as opposed to full market value. 

The Department of Conservation assists all levels of government, and landowners in the interpretation of the Williamson Act related government code.  The Department also researches, publishes and disseminates information regarding the policies, purposes, procedures, and administration of the Williamson Act according to government code.  Participating counties and cities are required to establish their own rules and regulations regarding implementation of the Act within their jurisdiction.  These rules include but are not limited to: enrollment guidelines, acreage minimums, enforcement procedures, allowable uses, and compatible uses.