A condominium (plural either condominia, as in Latin, or condominiums) in international law is a political territory (state or border area) in or over which multiple sovereign powers formally agree to share equal dominium (in the sense of sovereignty) and exercise their rights jointly, without dividing it into "national" zones.

Although a condominium has always been recognized as a theoretical possibility, condominia have been rare in practice. A major problem, and the reason so few have existed, is the difficulty of ensuring cooperation between the sovereign powers; once the understanding fails, the status is likely to become untenable.

The word is recorded in English since about 1714, from Modern Latin, apparently coined in Germany about 1700 from Latin com- "together" + dominium "right of ownership" (compare domain). A condominium of three sovereign powers is sometimes called a tripartite condominium or tridominium.

Real estate is property consisting of land and the buildings on it, along with its natural resources such as crops, minerals or water; immovable property of this nature; an interest vested in this (also) an item of real property, (more generally) buildings or housing in general.

Real estate is different from personal property, which is not permanently attached to the land, such as vehicles, boats, jewelry, furniture, tools and the rolling stock of an agricultural farm.