Home rule is government of a colony, dependent country, or region by its own citizens. It is thus the power of a part (administrative division) of a state or an external dependent country to exercise such of the state's powers of governance within its own administrative area that have been decentralized to it by the central government.

In the British Isles, it traditionally referred to self-government, devolution or independence of its constituent nations—initially Ireland, and later Scotland, Wales, and Northern Ireland. In the United States and other countries organised as federations of states, the term usually refers to the process and mechanisms of self-government as exercised by municipalities, counties, or other units of local government at the level below that of a federal state (e.g., US state, in which context see special legislation). It can also refer to the system under which Greenland and the Faroe Islands are associated with Denmark.

Home rule is not, however, equivalent to federalism. Whereas states in a federal system of government (e.g., Canada, Germany, Switzerland, Brazil, Ethiopia and the United States) have a guaranteed constitutional existence, a devolved home rule system of government is created by ordinary legislation and can be reformed, or even abolished, by repeal or amendment of that ordinary legislation.

A legislature may, for example, create home rule for an administrative division, such as a province, a county, or a department, so that a local county council, county commission, parish council, or board of supervisors may have jurisdiction over its unincorporated areas, including important issues like zoning. Without this, the division is simply an extension of the higher government. The legislature can also establish or eliminate municipal corporations, which have home rule within town or city limits through the city council. The higher government could also abolish counties/townships, redefine their boundaries, or dissolve their home-rule governments, according to the relevant laws.