Administrative divisions of Massachusetts

Massachusetts shares with the five other New England states a governmental structure known as the New England town. Only the southeastern third of the state has functioning county governments; in western, central, and northeastern Massachusetts, traditional county-level government was eliminated in the late 1990s. Generally speaking, there are four kinds of public school districts in Massachusetts: local schools, regional schools, vocational/technical schools, and charter schools.

In many other states, a town is a compact incorporated area; between the towns are unincorporated areas, usually quite large, that do not belong to any town. Such states are completely apportioned into counties, and county governments have significant importance, particularly to those living outside towns, and often perform major functions such as providing police and fire services and operating airports.

In contrast, all of the land in Massachusetts is divided up among the cities and towns and there are no "unincorporated" areas or population centers, nor townships. (This is generally true of most of the New England states, and is described at length at New England town.) This complicates comparisons with other non-New England states. The U.S. Census Bureau considers Massachusetts cities and towns to be minor civil divisions, equivalent to townships in other states, but townships usually have weaker forms of government. Many Massachusetts residents also identify with neighborhoods, villages, or other districts of their towns and cities.

Many municipalities have their own police departments, as do many Massachusetts colleges and universities.Massachusetts State Police have sole authority under state law for investigating homicides, except for Boston, Worcester, and Springfield. Fire protection is generally also provided by municipal fire departments. Massport has its own fire department, and its Fire Rescue provides protection on agency property. Fire departments have mutual aid agreements, such as the Massachusetts Metro Fire District in Greater Boston, which facilitate emergency response across department boundaries.

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