New Jersey's practical reality is dominated by its roughly 565 municipalities and townships, which under the state's strong "home rule" tradition handle most everyday local services — that's usually who a resident should contact first. At the county level, most counties (16 of 21) use a traditional elected Board of County Commissioners that exercises executive functions through an appointed administrator; five more populous counties (Atlantic, Bergen, Essex, Hudson, and Mercer) instead elect a separate County Executive with independent authority. Counties handle courts, jails, roads and bridges, social services, and election administration.

Most states put the bulk of local governance at the county level under a small elected commission board; New Jersey instead splits real authority between hundreds of independently powerful municipalities (its dominant "home rule" pattern) and a county layer that itself varies in structure from county to county.