The Partnership HealthPlan of California, "The HealthPlan," began operations in May 1994, and is a public/private organization designed to provide a cost-effective health care delivery system to Medi-Cal recipients in California 's Solano, Napa, and Yolo Counties. The HealthPlan's goals are to improve access, quality and cost effectiveness, through a managed care system. The HealthPlan links each member with a primary care provider and has been successful in reducing inappropriate emergency room usage, providing an appropriate level of inpatient care, developing innovative case management programs and providing more services locally.

The HealthPlan is an outgrowth of a local coalition of representatives from the County Medical Society, Kaiser Permanente, NorthBay Healthcare Systems, Sutter Solano Medical Center, Solano County Department of Health & Social Services, the Agricultural Workers' Health Center of Dixon, Vacaville Community Clinic, Planned Parenthood, the Council of Cities, and the Solano County Office of Education. These representatives became The Solano Coalition for Better Health. The Coalition was formed in 1988 to address the problem of health care to access for the country's growing number of medically uninsured and underserved.

Under State law, the Solano, Napa, and Yolo County Boards of Supervisors created a "health authority" with quasi-independent political jurisdiction to contract with the State for managing the care of the county's Medi-Cal beneficiaries and to oversee operation of The HealthPlan. The HealthPlan is organized as a "health insuring organization," and is legally a subdivision of the State of California, but is not part of any city, county or state government system.

After its founding in 1994 in Solano County, The HealthPlan expanded into neighboring Napa County in 1998 and Yolo County in 2001. The HealthPlan's Commission, or Board of Directors, expanded from 14 to 22 members to include new representatives from Napa and Yolo Counties. The Solano, Napa, and Yolo County Board of Supervisors appoint the HealthPlan's Commission, including: consumer, community, business, nurse, physician, hospital, health maintenance organization, community clinic, local government and County Health Department representatives. Today, The HealthPlan serves over 85,000 members.

The HealthPlan has also been involved in several community healthcare programs other than Medi-Cal. In 2002 PHC began to serve 2,600 County Medical Services Program members in Solano County. Through The HealthPlan, these members were able to receive both primary and specialty care through The HealthPlan's network of physicians. Eventually the pilot program served 5,200 Solano County CMSP members until the program ended in Fall 2005.

In November 2005 The HealthPlan was licensed by the California Department of Managed Health Care (DMHC) to offer a Healthy Kids program. The regional approach, the first of its kind in California, was launched over a two month period beginning in December 2005 in Solano, Napa, Yolo, and Sonoma Counties. The Healthy Kids program offers comprehensive health coverage to children 0 to 18 years of age, and who are ineligible for other publicly-funded programs such as Medi-Cal and Healthy Families. Funding is sustained through member premiums and fundraising from the California and County First 5 Initiatives, County Children's Health Initiatives, the California Endowment, the California HealthCare Foundation (CHCF), Blue Cross of California Foundation, and various regional donors.

Through these efforts, The HealthPlan continues to strive to achieve its goal of helping the members and the communities it serves be healthy.