Health-insuring organizations that are organized and operated by a governing board appointed by the county’s Board of Supervisors. All Medi-Cal beneficiaries residing within the county are required to enroll unless they have a voluntary aid code, which allows them to enroll in fee-for-service Medi-Cal. The first plan was implemented in Santa Barbara County in 1983. Five County Organized Health Systems plans operate in eight counties: Monterey, Napa, Orange, San Mateo, Santa Barbara, Santa Cruz, Solano, and Yolo.