CalOptima is a County Organized Health System authorized by federal law to administer Medi-Cal benefits for Orange County residents. It is governed by a board of directors and manages the health care for approximately 330,000 people in Medi-Cal, Medicare, California's Healthy Families and Healthy Kids programs in Orange County.

Since opening its doors in October of 1995, CalOptima has greatly improved access to health care for thousands of the county's poor, disabled, and aged residents. Operating with a $800 million annual budget, CalOptima contracts with 11 health networks to provide health care to approximately 330,000 members. It participates in California's Healthy Families program and has the largest enrollment of any Healthy Families program with more than 30,000 children enrolled. CalOptima's OneCare program provides coverage for people who qualify for Medicare and Medi-Cal benefits and has more than 7,000 members enrolled in the program.