Municipal annexation is the legal process by which a city acquires land.
Within areas that are subdivided noncontiguously, annexation can take place whereby a lower-tier subdivision can annex territory under the jurisdiction of a higher-tier subdivision. For example, in the United States, incorporated cities and towns often expand their boundaries by annexing unincorporated land adjacent to them. Municipalities can also annex and be annexed by other municipalities, though this is less common in the United States. Laws governing the ability and the extent cities can expand in this fashion are defined by the individual states' constitutions.
Annexation of neighbouring communities occurs in Canada. The city of Calgary, for example, has in the past annexed the communities of Bridgeland, Riverside, Sunnyside, Hillhurst, Hunter, Hubalta, Ogden, Forest Lawn, Midnapore, Shepard, Montgomery, and Bowness.