Five elected Supervisors, who each hold a four-year term, oversee Ventura County. They choose department heads who oversee county operations. Due to a large image of Junpero Serra that might offend those who believe Serra was responsible for the repression of the Chumash people's culture, the county seal, which was established in 1964, was examined in 2022. Additionally, the seal included representations of the county businesses that no longer exist, like as nuclear power and oil drilling. Arch Rock, off Anacapa Island, is featured on a new seal that was accepted.
The Ventura County Sheriff also contracts with the incorporated cities of Thousand Oaks, Fillmore, Camarillo, Moorpark, and Ojai to provide court protection, county jail management, and patrol for the unincorporated regions of the county. Municipal police divisions are present in the incorporated cities of Ventura, Oxnard, Simi Valley, Port Hueneme, and Santa Paula.
East County and West County, which are divided by the Conejo Grade, are the two main divisions of Ventura County. All of the cities east of the Conejo Grade are included in East County. East County is the terminus of the Santa Monica Mountains, where the Conejo Valley is situated and there is a significant elevation increase. Thousand Oaks, Newbury Park, Lake Sherwood, Hidden Valley, Santa Rosa Valley, a portion of Westlake Village, Oak Park, Moorpark, and Simi Valley are all regarded as being in the East County. The Conejo Valley is home to the bulk of these settlements.
The U.S. 101 corridor experienced more development, which caused population growth in West County cities as well. In Camarillo, Oxnard, and Ventura, there has been the greatest population growth. Since the majority of these cities, including Thousand Oaks and Simi Valley, are getting close to build-out, development in the East County and along the US 101 corridor is now unusual. Although there is still a lot of open space and land in the area, it is virtually entirely enclosed by greenbelts that run between the cities.