An easement is a nonpossessory right to use and/or enter onto the real property of another without possessing it. It is "best typified in the right of way which one landowner, A, may enjoy over the land of another, B". An easement is a property right and type of incorporeal property in itself at common law in most jurisdictions.

An easement is similar to real covenants and equitable servitudes. In the United States, the Restatement (Third) of Property takes steps to merge these concepts as servitudes.

Easements are helpful for providing access across two or more pieces of property, allowing individuals to access other properties or a resource, for example to fish in a privately owned pond or to have access to a public beach.

The rights of an easement holder vary substantially among jurisdictions.

Types:

Historically, common law courts would enforce only four types of easement:

Right-of-way (easements of way).

Easements of support (pertaining to excavations).

Easements of "light and air", and,

Rights pertaining to artificial waterways.

Courts now recognize more varieties of easements, but these original categories still form the foundation of easement law.

Affirmative and negative easements:

An affirmative easement is the right to use another property for a specific purpose while a negative easement is the right to prevent another from performing an otherwise lawful activity on their own property. For example, an affirmative easement might allow land owner A to drive their cattle over the land of B. A has an affirmative easement from B. Conversely, a negative easement might restrict land owner A from putting up a wall of trees that would block the adjacent land owner B's mountain view. A is subject to a negative easement from B.

Dominant and servient estate:

As defined by Evershed M R in Re Ellenborough Park, an easement requires the existence of at least two pieces of land. The land with the benefit of the easement is the dominant estate or dominant tenement, while the land burdened by the easement is the servient estate or servient tenement. For example, the owner of parcel A holds an easement to use a driveway on parcel B to gain access to A's house. Here, parcel A is the dominant estate, receiving the benefit, and parcel B is the servient estate, granting the benefit or suffering the burden.

Public and private easements:

A private easement is held by private individuals or entities. A public easement grants an easement to the public, for example, to allow public access over a parcel owned by an individual.

Appurtenant and in gross easements:

In the US, an easement appurtenant is one that benefits the dominant estate and "runs with the land" and so generally transfers automatically when the dominant estate is transferred. An appurtenant easement allows property owners to access land that is only accessible through a neighbor's land.

Conversely, an easement in gross benefits an individual or a legal entity, rather than a dominant estate. The easement can be for a personal use (for example, an easement to use a boat ramp) or a commercial use (for example, an easement to a railroad company to cross property to build and maintain a rail line). Historically, an easement in gross was neither assignable nor inheritable, but commercial easements are now freely transferable to a third party. They are divisible but must be exclusive (the original owner no longer uses it and exclusive to the easement holder) and all holders of the easement must agree to divide. If subdivided, each subdivided parcel enjoys the easement.