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An Easement that is implied into the conveyance of a piece of land, without which the land conveyed would essentially be worthless. Easements of necessity frequently take the form of an easement of access -- if I sell a piece of land that is surrounded on all sides by land that I still own, I can hardly expect the purchaser to buy a helicopter to get to his land.

-- Main.KevinBoone - 15 Jan 2004