The Planning Commission is charged with carrying out the purposes of California Planning and Zoning Law. Primarily this means that the Planning Commission implements plans, ordinances and policies relating to land use matters. They assist in writing and implementing the General Plan and area plans, and hold public hearings on the plans. They hold hearings and act on proposed changes to the Zoning Code, Zoning Map and the General Plan. They hold hearings and act on tentative subdivision maps, and they undertake special planning studies as needed.