The principal units of local government in 2002 were the 22 cities and 467 townships. There were 99 public school districts and 222 special districts that year. As is customary in New England, the basic instrument of town government is the annual town meeting, with an elective board of selectmen supervising town affairs between meetings; some of the larger towns employ full-time town managers. Maine's 16 counties (2002) function primarily as judicial districts.