In California, through the Subdivision Map Act, the state legislature gave cities and counties the power to regulate the subdivsion of tracts of land and to control the design and improvement of subdivisions.

To gain approval to subdivide land, a developer submits a tentative map of the proposed subdivision to the city or county.

City or county staff examine the design of the subdivision to ensure that it meets the requirements of the city or county's general plan and its subdivision ordinance.

If the proposed subdivision has the potential to have a significant adverse impact on the environment, city or county officials assess the environmental characteristics of the site and determine what effects or impacts will result if the site is altered or disturbed. They identify measures to avoid or reduce those impacts.

Before city or county officials approve a tenative subdivision map, they advertise and hold a public hearing. At the hearing, citizens and community groups can express their concerns about the subdivision and recommend changes to the proposed design.

Officials generally make approval of subdivision maps conditional upon the developer providing public improvements such as streets, drainage facilities, water supply or sewer lines to serve the subdivision. They also may require a developer to dedicate park land to the community.

The developer must install these improvements or secure them by bond before the city or county will grant final map approval.

The developer has at least two years (plus extensions) in which to comply with the improvement requirements, gain final administrative approval and record the final map.

When the developer satisfies all of the conditions set out in the approved tentative map and city or county officials have certified compliance, the city council or county board of supervisors will approve a final map.

Unlike a tentative map, which can be denied if it does not meet city or county standards, the final map must be approved (with some exceptions) if it substantially complies with the previously approved tentative map.

Upon approval of the final map, the developer may record it at the County Recorder's office. Lots within the subdivision cannot be sold and are not legal divisions of land until a final map has been recorded.

Subdivision Map Act of the California Government Code