Local government, the level closest to citizens' input, differs in communities across the United States. Most city and town governments, though, contain a legislative, an executive, and a judicial branch, just as do the federal and state governments. Most cities and towns are governed by some form of elected city council and a mayor. Beginning in the Progressive era of the early twentieth century, many cities began to hire city managers, professionals with expertise in budgeting and services, in an effort to reduce political corruption in city governments and because modern cities were becoming so large and complex that a new area of expertise seemed necessary in order to manage them.
City governments differ widely, just as cities do. In some states, the tradition of local government is strong, and local governments possess considerable powers, while in other states more decisions are made at the level of state government. Many towns are small, but the nation's largest cities, such as New York City, have more inhabitants than many states. In these large cities, which are often surrounded by suburbs, relations between city and suburbs are crucial to the vitality and success of the entire urban area.
Local government provides many essential services on which citizens depend. Perhaps most important, local communities oversee public schools, about which parents, students, and other citizens care deeply. In most communities the local school board, which oversees the management of the school system, is elected by voters, while in other communities board members are appointed by the mayor.