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To have an interest in land or property 'in possession' is to be in a position to enjoy the benefits of that interest right now. Otherwise, an interest is said to be 'in remainder'. Both terms are normally used of Freehold interests. Under the current legislation, only 'in possession' interests are conveyable.

Another term for an 'in possession' interest, commonly used when speaking of a Trust, is a 'Vested interest'. This term is used not only of land and property, but of the income arising from land or property, and for other, lesser interests.