Johnson County is currently composed of 11 cities: Iowa City, Coralville, Lone Tree, Tiffin, Oxford, North Liberty, Shueyville, University Heights, Hills, Swisher, Solon and a subdivision of West Branch. Johnson County is home to more than 100,000 Iowans and a wide variety of businesses, including farming, retail, manufacturing and academics.

The county government's responsibilities range from roads and bridges to human services, law enforcement, parks and natural resources. Iowa City is the seat of Johnson County and, as such, many of the county government offices are located there.